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                                                                   EXHIBIT 10.21

   
[*] Confidential Treatment has been requested for certain portions of this 
    exhibit. 
    

                                                                   April 1, 1997

[NBC LETTERHEAD]

Federal Express
Mr. Peter Ellis
President/CEO
Auto-By-Tel
11872 MacArthur Blvd., Second Floor
Irvine, CA 92612

           Re: Auto-By-Tel Participation in NBC Syndication Platform

Dear Mr. Ellis:

      This Letter sets forth the initial agreement between NBC Multimedia, Inc.
("NBC"), and Auto-By-Tel Marketing Corporation ("Company") with respect to the
Company's agreement to provide content as part of NBC's Syndication Platform.
The terms and conditions shall be as follows:

1.    Description of NBC Syndication Platform: NBC intends to create a menu of
      localized world wide web services (the "NBC Syndication Platform") which
      it will offer to the NBC Television Network's ("NBC TV") owned and
      operated stations and interested affiliates (the "Stations"). NBC agrees
      that if it does actually offer the NBC Syndication Platform, localized
      versions of the Auto-By-Tel online automotive information, purchasing
      financing and related services created and operated by the Company
      ("Auto-By-Tel") shall be among the list of primary services offered as
      part of such platform subject to the terms and conditions hereof. Company
      acknowledges (i) that each Station will have the sole right to determine
      which individual services it will accept as part of the NBC Syndication
      Platform, (ii) that Auto-By-Tel may or may not be included in any
      individual Station's list of such services, and (iii) that NBC and
      declining Stations shall have no liability or obligations to Company due
      to any Stations' decision not to so include Auto-By-Tel.

2.    Creation of Auto-By-Tel Local Sites: Company agrees that it shall create
      customized local versions of Auto-By-Tel (each a "Auto-By-Tel Local
      Site") for use by Stations participating in the NBC Syndication Platform.
      Such Auto-By-Tel Local Sites will be designed to provide online viewers
      of the Stations' world wide web sites (the "Station Sites") with
      automotive information and purchasing financing and related services.
      Each such Auto-By-Tel Local Site shall be a mirror Auto-By-Tel site which
      shall be framed within a sub-page of the Station Site but which will
      contain material to be provided by Company and located at a to be
      established URL on a server of the Company. As a result, all online
      viewers will be accessing and bookmarking the Auto-By-Tel Local Site
      content through the NBC Syndication Platform's portion of the Station's
      URL, and any user searches will continue to take place within the portion
      of the Station Site framing the Auto-By-Tel Local Site.

3.    Links: As a condition of utilizing the NBC Syndication Platform, each
      participating Station will be required to devote a portion of the front
      page of the Station Site to the NBC Syndication Platform, subject to
      Station's right to have overall design control of the Station Site. Each
      Station shall be encouraged to devote enough space on its front page to
      permit the placement of hotlinks to the individual services which make up
      the NBC Syndication Platform within space on such front page allocated
      and dedicated to the NBC Syndication Platform, but at a minimum, each
      participating Station Site's front page shall contain a prominent hotlink
      to a special sub-page devoted to hotlinks for all of the services making
      up the NBC Syndication Platform, the size and placement 
 
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      of which shall be comparable to that of any other link to a service
      offered by the Station. NBC agrees that when the individual services which
      make up the NBC Syndication Platform are displayed and a hotlink to the
      Auto-By-Tel Local Site is provided, whether on a front page or on a
      separate page, the link to the Auto-By-Tel Local Site which may be either
      a generic category description or a Auto-By-Tel logo or text (the
      "Auto-By-Tel Link") shall be comparable and consistent with the links
      devoted to any of the other individual services which are part of the NBC
      Syndication Platform.

4.    Management of Auto-By-Tel Local Sites:  The day-to-day management of the
      Auto-By-Tel Local Sites, and all costs associated therewith, shall be the
      responsibility of the Company subject to the following:

      (a) Content - Company will provide all of the content for each of the
      Auto-By-Tel Local Sites, provided that as part of the localization and
      customizing process required herein, NBC and the Stations may provide
      relevant local material (but not advertising) in their own discretion from
      time to time with reasonable notice for use on the relevant Auto-By-Tel
      Local Sites and Company will make good faith efforts to include such
      material in its reasonable discretion. Company will acquire all necessary
      rights and licenses required for the operation of each Auto-By-Tel Local
      Site as contemplated herein and for the acquisition and use of any content
      (e.g., automobile purchase analyses, appreciation costs, financing
      incentives, etc.) not provided by NBC and the Stations. Each of the
      Company, NBC and the Stations will retain and own all copyrights and other
      intellectual property rights in, and to, the material which that entity
      contributes for use hereunder.

      (b) Editorial - Editorial standards and direction regarding the inclusion
      and presentation of content will come from Company. In addition, Company
      agrees to allow NBC to review the Auto-By-Tel Local Sites for compliance
      with any NBC Broadcast Standards and Practices which may apply to the
      Auto-By-Tel Local Sites and make all changes requested by NBC in
      connection therewith. Finally, Company agrees to comply with any Rules and
      Regulations of the Federal Communications Commission which may be
      applicable to the Auto-By-Tel Local Sites and/or the rules and regulations
      of any other governmental body having jurisdiction.

      (c) Technology - Auto-By-Tel shall be responsible for all maintenance of
      the Auto-By-Tel Local Sites (including customer service, technical upkeep,
      etc.) including the costs associated therewith. Auto-By-Tel agrees to use
      its best efforts to work with NBC's technology partners to coordinate the
      interface between the Auto-By-Tel Local Sites and the Station Sites and
      provide the required services contemplated herein.

      (d) Branding - NBC shall create the Auto-By-Tel Link and may request that
      Company provide appropriate proprietary material for use thereon. The
      Auto-By-Tel Local Sites will be co-branded with trademarks and other
      material to be provided by NBC, the Stations and Company subject to the
      approval of each party and provided that the size of such brands shall be
      left to the reasonable discretion of NBC. The parties agree that the
      Company's brands on the Auto-By-Tel Local Sites shall be not more than
      fifty percent (50%) smaller than, but as visible as, the brands of NBC and
      the relevant Stations. Company agrees to abide by all requirements and
      guidelines which NBC and the Stations may have regarding the use of their
      trademarks, service marks and other brands and agrees that it shall make
      no use of such marks and brands which is not approved in advance by NBC
      and the relevant Stations. Branding for all other areas of the NBC
      Syndication Platform and the Station Sites shall be at the sole discretion
      of NBC and the Stations.

5.    Promotion: As a condition of utilizing the NBC Syndication Platform, each
      Station will be required of offer a minimum of 10 on-air promos
      concerning, or mentions of,


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        the URL address of the Station Site per week. NBC shall encourage
        Stations to include information regarding the NBC Syndication Platform
        as part of such promos or mentions.

   
6.      Exclusivity: NBC agrees that Auto-By-Tel will be the exclusive service
        provider for the online automotive purchasing and information category
        of the NBC Syndication Platform offered by NBC, provided that Company
        acknowledges that nothing in this Section 6 or elsewhere in the Letter
        Agreement shall restrict NBC rights in any way in connection with NBC's
        world wide web site ("NBC.com"), MSNBC.com, Intellicast.com or any
        other future NBC related interactive (or other) services other than the
        NBC Syndication Platform. Notwithstanding the foregoing, Company
        acknowledges that (i) other services provided by third parties may be
        offered to the Stations by NBC as part of the NBC Syndication Platform
        which happen to provide online automotive information in addition to
        their primary services as long as NBC does not offer such third party
        services in place of Company's services on the NBC Syndication Platform
        or materially promote such competing aspects of such third party
        services to the Stations or the public (other than through general
        advertising) in connection with the NBC Syndication Platform and (ii)
        NBC will have no ability to prevent the Stations from placing competing
        services elsewhere on their own Station Sites. Company agrees that NBC
        will be the exclusive United States television distribution partner for
        Auto-By-Tel's content and service, and Company agrees not to provide
        the Auto-By-Tel service, or any portion thereof, to national or
        regional television networks, syndicated programming services or
        syndicated or like content platforms distributed by or through the
        foregoing; provided, however, that NBC recognizes that such exclusivity
        shall not prevent Company from providing the Auto-By-Tel service to any
        internet service provider which uses televisions as a delivery device
        (i.e., Web TV). The exclusivity terms of this Paragraph 6 will be
        contingent upon NBC's reaching and then maintaining over each following
        year on average the following critical mass of Station support for the
        NBC Syndication Platform: [*] If such contingencies are not
        met, the exclusivity terms of this Section 6 shall no longer apply,
        but all other terms of this Letter Agreement shall remain in effect
        until the termination hereof. In addition, if Company is not able to
        provide competitive, localized coverage and service for any of the NBC
        TV markets, NBC will be free to contract with Company's competitors in
        order to obtain online automotive information in such markets.

7.      Advertising Sales: Company shall be responsible for the sale of
        advertising inventory to be placed on each Auto-By-Tel Local Site, if
        any. Company shall have the responsibility of administering the contract
        for such advertising, paying all necessary expenses and collecting all
        fees related thereto in return for a seller's commission of [*] of the
        gross advertising revenues related to such sale (the "Sales
        Commission"). Unless the parties mutually agree to the contrary, if
        Company decides in its sole discretion to sell advertising inventory for
        the Auto-By-Tel Local Sites at less than the rates normally charged by
        Company for advertising appearing elsewhere on Auto-By-Tel (the "Normal
        Rates") or barters such inventory in any way, such advertising inventory
        shall be deemed to have been sold at such Normal Rates for purposes of
        calculating revenues for purposes of Section 8(b) below. Company
        acknowledges that NBC and the Stations will be solely responsible for
        the sale of advertising which appears within the area of the Station
        Sites which frames Auto-By-Tel Local Sites and that Company will have no
        right to advertising revenues received by NBC and Stations in connection
        with such frames or any other portions of the
    


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      Station Sites other than the Auto-By-Tel Local Sites. NBC acknowledges
      that manufacturers' financing and insurance products or services offered
      through the Auto-By-Tel Local Site shall not be deemed advertising for
      the purposes hereof.

8.    Financial Terms: Company agrees that it will be responsible for all costs
      and expenses associated with the creation and operation of the Auto-By-Tel
      Local Sites. Auto-By-Tel shall make the following monthly payments to NBC.

   
      (a)   Annual License Fee - Company will pay NBC a license fee of [*]
      hereof and upon each anniversary date of the launch of the NBC Syndication
      Platform occurring during the term hereof. This fee shall also be
      considered a non-refundable advance on any revenues payable to NBC in
      connection with the terms of sub-section (c) of this Section 8.
    

      (b)   Advertising Revenues - NBC and Company will equally share (i.e.,
      50/50) all gross revenues received by Company in connection with the sale
      of advertising for display anywhere within the Auto-By-Tel Local Sites
      after deduction of the Sales Commission is made but prior to the
      deduction of any expenses of any kind.

   
      (c)   Lead Generation Revenues - Company will pay NBC [*] for each online
      or physical (e.g., mail, fax, etc.) submission of any "unique purchase
      request" to Auto-By-Tel by any individual or corporate user which is
      received by Company and attributable to usage on an Auto-By-Tel Local
      Site. "Unique purchase request" shall mean a purchase request from a user
      with a different name and e-mail address from any name or address received
      by Company in the past. In addition, once the Auto-By-Tel Local Sites
      generate [*] such submissions in any calendar year during the term hereof,
      then Company will pay NBC [*] for each such submission received thereafter
      until the end of that calendar year. The parties agree that the Annual
      License Fee described above shall be an advance against payments for the
      first [*] submissions otherwise owed hereunder.
    

      (d)   Future Revenue - The parties agree that if any future revenue
      generating opportunities not engaged in by Company through its
      Auto-By-Tel service as of the date hereof or described above are created
      in connection with the Auto-By-Tel Local Sites, the parties will
      negotiate in good faith regarding what revenue sharing arrangements
      between the parties would be appropriate, provided that, unless such
      opportunities involve characteristics which would make them materially
      different from the opportunities described above, it is the intent of the
      parties to share such revenues equally.

9.    Payment and Audit Conditions. At the end of each month in which Company
      receives any revenue of the type described in Section 8 (b) and (c),
      Company shall prepare a monthly statement providing sufficient detail
      regarding the source of such revenue and will deliver such statement
      along with the required payment described therein to NBC no less than
      thirty (30) days following such date. Company agrees that NBC shall have
      the right to conduct a reasonable audit of the relevant books and records
      of such party in order to determine compliance with the terms of this
      Letter Agreement. The parties agree that all amounts due under this
      Agreement from the Company to NBC shall be paid directly to NBC and not
      to any of the individual Stations.

10.   Representations and Warranties: (a) Company represents and warrants to
      NBC and the Stations that it has the right and power to perform its
      obligations and to grant the rights granted herein, that Company's
      creation and operation of the Auto-By-Tel Local Sites pursuant to this
      Letter Agreement will not violate any agreement or obligation between
      Company and a third party or any laws or regulations and that, except for
      material provided by NBC and the Stations, the material included on the
      Auto-By-Tel Local Sites and the Auto-By-Tel Link as well as the operation
      of the Auto-By-Tel 

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      Local Sites as contemplated herein will, to the best of its knowledge, be
      accurate and correct and will not violate or infringe any third party
      rights, including intellectual property rights. Company also agrees that
      standard software industry representation and warranties will apply to
      all software and technology used by Company in order to carry out its
      obligations described herein. Company acknowledges that the Final
      Agreement (as defined below) will contain additional and more detailed
      versions of the representations and warranties described above.

      (b)   NBC represents and warrants to Company that it has the right and
      power to perform its obligations and to grant the rights granted herein
      and that the material provided by NBC to Company for inclusion on the
      Auto-By-Tel Local Sites will, to the best of its knowledge, be accurate
      and correct and will not violate or infringe any third party rights,
      including intellectual property rights.

11.   Indemnity. (a) Company agrees to indemnify, defend, and hold NBC, the
      Stations, their affiliates and their successors, officers, directors and
      employees harmless from any and all actions, causes of action, claims,
      demands, costs, liabilities, expenses (including reasonable attorneys'
      fees) and damages arising out of or in connection with any third party
      claims (i) relating to Company's operation and management of the
      Auto-By-Tel Local Sites, or (ii) relating to a breach of any of Company's
      representations and/or warranties set forth in Section 10 of this Letter
      Agreement.

      (b)   NBC agrees to indemnify, defend, and hold Company, its affiliates
      and its successors, officers, directors and employees harmless from any
      and all actions, causes of action, claims, demands, costs, liabilities,
      expenses (including reasonable attorneys' fees) and damages arising out
      of or in connection with any third party claims relating to a breach of
      any of NBC's representations and/or warranties set forth in Section 10 of
      this Letter Agreement.

      (c)   The indemnified party agrees to notify the other party promptly of
      any written claims or demands against the indemnified party for which the
      other party is responsible, and the Indemnified Party for which the other
      party will be entitled, at its option, to assume the defense or
      settlement of any such claim, provided that no settlement shall be
      reached without the consent of the indemnifying party. The indemnified
      party will promptly be reimbursed by the other party for Indemnified
      Amounts as they are incurred.

      (d)   IN NO EVENT UNDER ANY CIRCUMSTANCES SHALL EITHER PARTY (OR ITS
      AFFILIATES) BE LIABLE TO THE OTHER PARTY FOR ANY SPECIAL, INCIDENTAL,
      CONSEQUENTIAL OR PUNITIVE DAMAGES ARISING OUT OF OR IN CONNECTION WITH ITS
      OBLIGATION UNDER THIS LETTER AGREEMENT; PROVIDED HOWEVER, THAT THE
      FORGOING LIMITATION SHALL NOT APPLY TO DIRECT DAMAGES RESULTING FROM THE
      INTENTIONAL OR WILLFUL BREACH OF THIS LETTER AGREEMENT.

   
12.   Term. The initial term of this Letter Agreement shall be [*],
      and ninety (90) days prior to the end of the initial term, the parties
      agree to negotiate in good faith regarding a possible extension of the
      term hereof for an additional [*]. Either party may terminate
      this Letter Agreement upon a material default by the other party of the
      terms hereof which default is not cured within thirty (30) days following
      such party's receipt of a written notice regarding the default. In
      addition, if Company materially alters the nature or quality of its
      service (e.g., changes Auto-By-Tel from a free to subscription service),
      NBC may terminate this Letter Agreement, at its option, by providing
      Company with ten (10) days prior notice thereof in writing. Finally, if
      NBC determines in its sole discretion at any time, not to offer the NBC
      Syndication Platform as such term is described in Paragraph 1, it will
      inform the Company of such 
    

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     decision in writing and this Letter Agreement shall be deemed terminated as
     of the date of such notice.

13.  Formal Agreement. Recognizing that time is of the essence, this Letter
     Agreement shall serve as the intent of both parties to enter into a more
     formal agreement for the creation and operation of Auto-By-Tel Local Sites
     (the "Final Agreement"). Both parties shall use reasonable efforts to
     complete the Final Agreement within a reasonable time period following the
     date of execution of this Letter Agreement, provided, however, that
     notwithstanding the foregoing, if no Final Agreement is reached, the terms
     contained herein shall govern the relationship between the parties for the
     Term.

14.  NBC Local Link. The parties agree that each Auto-By-Tel Local Site shall
     include a link (which may include an appropriate NBC logo) to the NBC
     Local section of NBC.com in its first page.

15.  Confidentiality. Neither party shall issue a press release or make any
     statement to the general public concerning this Letter Agreement, the NBC
     Syndication Platform or the Auto-By-Tel Local Sites, or the existence
     thereof, without the express prior written consent of the other; provided,
     however, that NBC agrees that Company may file this Letter Agreement with
     the Securities and Exchange Commission (the "SEC") if so required by the
     Securities Act of 1933 and Securities Exchange Act of 1934, in each case,
     as amended, the rules and regulations related thereto or any applicable
     state laws (the "Securities Laws") as long as Company agrees to use its
     best efforts to obtain confidential treatment of the economic and other
     material terms hereof under the Securities Laws and consult with NBC
     during the process.

16.  Miscellaneous. This Letter Agreement constitutes the entire agreement and
     understanding of the parties relating to the subject matter hereof and
     supersedes all prior and contemporaneous agreements, negotiations, and
     understandings between the parties, both oral and written, provided that
     the Non-Disclosure and Confidentiality Agreement between the parties shall
     remain in full force and effect. No waiver or modification of any
     provision of this Letter Agreement shall be effective unless in writing
     and signed by both parties. Any waiver by either party of any provision of
     this Letter Agreement shall not be construed as a waiver of any other
     provision of this Letter Agreement, nor shall such waiver operate as or be
     construed as a waiver of such provision respecting any future event or
     circumstance. This Letter Agreement shall be governed by and construed
     under the laws of the State of New York applicable to contracts fully
     executed in New York, without regard to New York conflicts law. The
     parties hereby consent to and submit to the jurisdiction of the federal
     and state courts located in the State of New York.

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     If you are in agreement with the above terms and conditions, please
indicate your acceptance by signing in the space provided below, and return one
original to me. This Letter Agreement shall be null and void if not signed
within 7 days of the date set forth above.

                                        Very truly yours,

                                        NBC MULTIMEDIA, INC.

                                        By: /s/ KEN KRUSHEL
                                           -------------------------------------

                                        Name:  Ken Krushel

                                        Title: Vice President

ACCEPTED AND AGREED;

AUTO-BY-TEL MARKETING
CORPORATION

By: /s/ MARK W. LORIMER
   -----------------------------------

Name:  Mark W. Lorimer

Title: Vice President, General Counsel
       and Secretary

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NBC must reach and maintain over each following year, on average, the following
critical mass:

   
[*]