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                                                                     EXHIBIT 4.3

                                                                            WD-1
                                               Initially Issued November 4, 1999

     THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR UNDER THE SECURITIES LAWS OF
CERTAIN STATES. THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON TRANSFERABILITY
AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS PERMITTED UNDER THE
ACT AND THE APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION OR
EXEMPTION THEREFROM. WARRANTHOLDERS SHOULD BE AWARE THAT THEY MAY BE REQUIRED TO
BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN INDEFINITE PERIOD OF TIME.
THE ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND
SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR
RESALE IS IN COMPLIANCE WITH THE ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

                            STOCK PURCHASE WARRANT
                   To Purchase Shares of Preferred Stock of
                             CARSDIRECT.COM, INC.


     For value received, CarsDirect.com, Inc., a Delaware corporation (the
"Company") hereby grants to Robert Brisco (the "Warrantholder"), and its
assigns, the right, upon the terms and subject to the conditions hereinafter set
forth, at any time during the period commencing on November 4, 1999 and ending
on the close of business on November 4, 2004, to subscribe for and purchase from
the Company up to 200,000 fully paid and nonassessable shares of Series D
Preferred of the Company at a purchase price per share of $15.76. The exercise
price and the number of shares for which the Warrant is exercisable shall be
subject to adjustment as provided herein.

     1.   Title of Warrant. Prior to the expiration hereof and subject to
          ----------------
compliance with applicable laws, this Warrant and all rights hereunder are
transferable, in whole or in part, at the office or agency of the Company
referred to in Section 2(a) below, by the registered holder hereof (the
"Holder") in person or by duly authorized attorney, upon surrender of this
Warrant and the Assignment Form attached hereto properly
endorsed.

     2.   Exercise of Warrant.
          -------------------

          (a) The purchase rights represented by this Warrant are exercisable by
the Holder, in whole or in part, at any time before the close of business on
November 4, 2004 by the surrender of this Warrant and the Notice of Exercise
attached hereto duly executed at the office of the Company (or such other office
or agency of the Company as it may designate in writing to the Holder at the
address of the Holder appearing on the books of the Company), and upon payment
of the Purchase Price of the shares thereby purchased (by cash, check, or
cancellation of indebtedness of the Company to the Holder, if any, at the time
of exercise in an amount equal to the purchase price of the shares thereby
purchased); whereupon the Holder shall be entitled to receive a certificate for
the
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number of shares of Series D Preferred Stock so purchased. The Company agrees
that upon due exercise of this Warrant by the Holder, the shares so purchased
shall be and be deemed to be issued to the Holder as the record owner of such
shares as of the close of business on the date on which this Warrant is
exercised.

          (b)  In lieu of the cash payment set forth in Section 2(a) above, the
Holder shall have the right ("Conversion Right") to convert this Warrant in its
entirety (without payment of any kind) into that number of shares of Series D
Preferred Stock equal to the quotient obtained by dividing the Net Value (as
defined below) of the Shares of Series D Preferred Stock underlying this Warrant
by the Fair Market Value (as defined below) of one share of Series D Preferred
Stock. As used herein, (A) the Net Value means the aggregate Fair Market Value
of the shares of Series D Preferred Stock subject to this Warrant minus the
aggregate purchase price; and (B) the Fair Market Value of one share of Series D
Preferred Stock means:

               (i)   if the exercise is in connection with a registered public
offering of the Company's Common Stock, the Fair Market Value of one share of
Series D Preferred Stock shall be the product of (x) the initial "Price to
Public" of one share of Common Stock specified in the final prospectus with
respect to the offering and (y) the number of shares of Common Stock into which
each share of Series D Preferred Stock is convertible at the time of such
exercise;

               (ii)  if the exercise is in connection with a merger, acquisition
or other consolidation pursuant to which the Company is not the surviving party,
the Fair Market Value of one share of Series D Preferred Stock shall be deemed
to be the value received by the holders of the Company's Series D Preferred
Stock on a common equivalent basis pursuant to such Merger Transaction; and

               (iii) in all other cases, the Fair Market Value of one share of
Series D Preferred Stock shall be the product of (x) the fair market value of
the Common Stock of the Company, as determined in good faith by the Company's
Board of Directors and (y) the number of shares of Common Stock into which each
share of Series D Preferred Stock is convertible at the time of such exercise.

          (c)  Certificates for shares purchased hereunder shall be delivered to
the Holder within a reasonable period of time after the date on which this
Warrant is exercised.

          (d)  The Company covenants that all shares of Series D Preferred Stock
which may be issued upon the exercise of this Warrant will be duly authorized,
validly issued, fully paid and nonassessable and free from all taxes, liens and
charges in respect of the issue thereof (other than taxes in respect of any
transfer occurring contemporaneously with such issue).

     3.   No Fractional Shares or Scrip. No fractional shares or scrip
          -----------------------------
representing fractional shares shall be issued upon the exercise of this
Warrant. With respect to any fraction of a share called for upon the exercise of
this Warrant, an amount equal to such fraction multiplied by the current
Purchase Price at which each share may be purchased hereunder shall be paid in
cash to the Holder.

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     4.   Charges, Taxes and Expenses. Issuance of certificates for shares of
          ---------------------------
Series D Preferred Stock upon the exercise of this Warrant shall be made without
charge to the Holder for any issue or transfer tax or other incidental expense
in respect of the issuance of such certificate, all of which taxes and expenses
shall be paid by the Company, and such certificates shall be issued in the name
of the Holder or in such name or names as may be directed by the Holder;
provided however that in the event certificates for shares of Series D Preferred
Stock are to be issued in a name other than the name of the Holder, this Warrant
when surrendered for exercise shall be accompanied by the Assignment Form
attached hereto duly executed by the Holder; and provided further that upon any
transfer involved in the issuance or delivery of any certificates for shares of
Series D Preferred Stock, the Company may require reimbursement for any transfer
tax.

     5.   Rights as Stockholders. This Warrant does not entitle the Holder to
          ----------------------
any voting rights or other rights as a stockholder of the Company prior to the
exercise hereof. Upon exercise of this Warrant, the Holder shall become entitled
to all rights provided to Series D Preferred Holders under the Fourth Amended
and Restated Investor Rights Agreement between the Company and certain
stockholders dated October 27, 1999.

     6.   Exchange and Registry of Warrant. This Warrant is exchangeable, upon
          --------------------------------
the surrender hereof by the Holder at the above-mentioned office or agency of
the Company, for a new Warrant of like tenor and dated as of such exchange. The
Company shall maintain at such office or agency a registry showing the name and
address of the Holder. This Warrant may be surrendered for exchange, transfer or
exercise, in accordance with its terms, at such office or agency of the Company,
and the Company shall be entitled to rely in all respects, prior to written
notice to the contrary, upon such registry.

     7.   Loss, Theft, Destruction or Mutilation of Warrant. Upon receipt by the
          -------------------------------------------------
Company of evidence reasonably satisfactory to it of the loss, theft,
destruction or mutilation of this Warrant, and in case of loss, theft or
destruction, of indemnity or security reasonably satisfactory to it, and upon
reimbursement to the Company of all reasonable expenses incidental thereto, and
upon surrender and cancellation of such Warrant, if mutilated, the Company will
make and deliver a new Warrant of like tenor and dated as of such cancellation,
in lieu of this Warrant.

     8.   Saturdays, Sundays, Holidays, etc. If the last or appointed day for
          ----------------------------------
the taking of any action or the expiration of any right required or granted
herein shall be a Saturday or a Sunday or shall be a legal holiday, then such
action may be taken or such right may be exercised on the next succeeding day
not a legal holiday.

     9.   Adjustment and Termination.
          --------------------------

          (a)  Reclassification, etc. If the Company at any time shall, by
               ----------------------
subdivision, combination or reclassification of securities or otherwise, change
any of the securities to which purchase rights under this Warrant exist into the
same or a different number of securities of any class or classes, the shares of
Series D Preferred Stock or other securities for which this Warrant is
exercisable shall thereafter be convertible into the kind and number of shares
of stock or other securities or property of the Company or otherwise to which
the Holder would have been entitled if immediately prior to such change the
Holder had acquired the shares of Series D Preferred Stock or

                                      -3-
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other securities for which this Warrant is exercisable. If shares of the
Company's Series D Preferred Stock or other securities purchasable hereunder are
subdivided or combined into a greater or smaller number of shares, or if the
number of shares of Common Stock outstanding is increased by a stock dividend
payable in shares of Common Stock, the Purchase Price under this Warrant shall
be proportionately reduced in case of subdivision of shares or proportionately
increased in the case of combination of shares. No adjustment on account of cash
dividends or interest on the Company's Series D Preferred Stock or other
securities purchasable hereunder will be made to the Purchase Price under this
Warrant.

          (b)  Notice of Adjustment. Upon any adjustment of the securities
               --------------------
issuable upon exercise of this Warrant the Purchase Price for the shares, and/or
any increase or decrease in the number of shares purchasable upon the exercise
of this Warrant, the Company shall give written notice thereof, by first class
mail, postage prepaid, addressed to the Holder at the address of the Holder as
shown on the books of the Company.

          (c)  Authorized Shares. The Company covenants that during the period
               -----------------
the Warrant is outstanding, it will reserve from its authorized and unissued
Series D Preferred Stock or other securities purchasable hereunder a sufficient
number of shares to provide for the issuance of Series D Preferred Stock or
other securities upon the exercise of any purchase rights under this Warrant.

     10.  No Impairment. The Company will not, by amendment of its Certificate
          -------------
of Incorporation or through any reorganization, recapitalization, transfer of
assets, consolidation, merger, dissolution, issuance or sale of securities or
any other voluntary action, avoid or seek to avoid, directly or indirectly, the
performance of any of the terms of this Warrant, but will at all times in good
faith take all necessary action to carry out all such terms. Without limiting
the generality of the foregoing, the Company (a) will not create any par value,
or increase the par value, of any shares of stock receivable on exercise of this
Warrant above the amount payable therefor on such exercise, and (b) will take
all such action as may be necessary or appropriate so that the Company may
validly and legally issue fully paid and nonassessable shares of stock on the
exercise of this Warrant. Notwithstanding the foregoing, in the event of (a) a
dissolution or liquidation of the Company, (b) a merger consolidation or other
acquisition in which the Company is not the surviving corporation, (c) the sale
of all or substantially all of the assets of the Company, (d) unless otherwise
determined by the Company's Board of Directors (the "Board") in its sole
discretion, any other transaction which qualifies as a corporate reorganization
within the meaning of Section 368(a) of the Internal Revenue Code of 1986, as
amended, wherein the stockholders of the Company no longer hold a majority of
the outstanding capital stock of the surviving entity then, with respect to a
corporate transaction of the type described above, this Warrant shall,
notwithstanding any contrary terms set forth herein, expire twenty (20) days
after the Warrantholder receives written notice of such transaction. Such notice
shall describe the transaction in detail reasonably sufficient to allow the
Warrantholder to analyze the material terms of the transaction.

     11.  Lockup Agreement. In consideration for the Company agreeing to its
          ----------------
obligations hereunder, the Warrantholder and each transferee of Warrantholder's
rights hereunder, agrees in connection with the first registration of the
Company's securities, upon the request of the Company or the underwriters
managing such underwritten offering of the Company's securities, not to sell,

                                      -4-
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make any short sale of, loan, grant, any option for the purchase of, or
otherwise dispose of any shares of Series D Preferred or other securities of the
Company (other than those included in the Registration) into which such Series D
Preferred Stock is convertible without the prior written consent of the Company
or such underwriters, as the case may be, for such period of time (not to exceed
one hundred eighty (180) days) from the effective date of such registration as
the Company or the underwriters may specify. The Warrantholder agrees that the
Company may instruct its transfer agent to place stop transfer notations in its
records to enforce the foregoing provisions.

     12.  Record Date.
          -----------

          (a)  If the Company shall fix a record date of the holders of Series D
Preferred Stock (or other stock or securities at the time deliverable on
exercise of this Warrant) for the purpose of entitling or enabling them to
receive any dividend (other than a stock dividend) or other distribution, or to
receive any right to subscribe for or purchase any shares of any class of any
other securities, or to receive any other right;

          (b)  In the event of any reorganization or recapitalization of the
Company, any reclassification of the capital stock of the Company, any
consolidation or merger of the Company with or into another corporation or any
transfer of all or substantially all of the assets of the Company to another
entity;

          (c)  In the event of the voluntary or involuntary dissolution,
liquidation or winding up of the Company or;

          (d)  If the Company has filed a registration statement under the
Securities Act of 1933, as amended, with the Securities and Exchange Commission
for an offering of the Company's capital stock.

     Then, in any such event, the Company will mail or cause to be mailed to the
Holder a notice specifying, as the case may be, (i) the date on which a record
is to be taken for the purpose of such dividend, distribution or right and
stating the amount and character of such dividend, distribution or right, (ii)
the date on which a record is to be taken for the purpose of voting on or
approving such reorganization, recapitalization, reclassification,
consolidation, merger, conveyance, dissolution, liquidation or winding up and
the date on which such event is to take place and the time, if any is to be
fixed, as of which the holders of record of Series D Preferred Stock (or such
other stock or securities at the time deliverable on exercise of this Warrant)
shall be entitled to exchange their shares of Series D Preferred Stock (or such
other stock or securities) for securities or other property deliverable on such
reorganization, recapitalization, reclassification, consolidation, merger,
conveyance, dissolution, liquidation or winding up or (iii) the date on which
the Company's registration statement was filed and the class of securities
proposed to be registered. Such notice shall be mailed at least twenty-one days
prior to the record date therein specified or within twenty-one days after
filing the registration statement, as the case may be.

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     13.  Miscellaneous.
          -------------

          (a)  Issue Date. The provisions of this Warrant shall be construed and
               ----------
shall be given effect in all respect as if it had been issued and delivered by
the Company on the date hereof. This Warrant shall be binding upon any
successors or assigns of the Company. This Warrant shall constitute a contract
under the laws of the State of California and for all purposes shall be
construed in accordance with and governed by the laws of said state.

          (b)  Restrictions. The Holder acknowledges that the securities
               ------------
acquired upon the exercise of this Warrant may have restrictions upon its resale
imposed by state and federal securities laws.

          (c)  Modification and Waiver. This Warrant and any provisions hereof
               -----------------------
may be changed, waived, discharged or terminated only by an instrument in
writing signed by the party against which enforcement of the same is sought.

          (d)  Notices. All notices, reports and other communications required
               -------
or permitted hereunder shall be in writing and may be delivered in person, by
telecopy with written confirmation, overnight delivery service or U.S. mail, in
which event it may be mailed by first-class, certified or registered, postage
prepaid, addressed to the Holder at its address as shown on the books of the
Company or to the Company at 10567 Jefferson Blvd., Culver City, CA 90232
Attention: President, with a copy to Martin W. Korman, Esq., Wilson Sonsini
Goodrich & Rosati, 650 Page Mill Road, Palo Alto, CA 94304.

               Each such notice, report or other communication shall for all
purposes under this Warrant be treated as effective or having been given when
delivered if delivered personally or, if sent by mail, at the earlier of its
receipt or 72 hours after the same has been deposited in a regularly maintained
receptacle for the deposit of the United States mail, addressed and mailed as
aforesaid, or, if sent by telecopier with written confirmation, at the earlier
of (i) 24 hours after confirmation of transmission by the sending telecopier
machine or (ii) delivery of written confirmation.


Dated:  November 4, 1999

                                     CARSDIRECT.COM, INC.


                                     By:    /s/ Frederick G. Silny
                                        -----------------------------------
                                     Name:  Frederick G. Silny
                                          ---------------------------------
                                     Title: Secretary
                                           --------------------------------

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                                ASSIGNMENT FORM

                   (To assign the foregoing Warrant, execute
                this form and supply the required information.
                   Do not use this form to purchase shares.)

         FOR VALUE RECEIVED, the undersigned hereby, sells, assigns and
transfers unto:

________________________________________________________________________________
whose address is________________________________________________________________
                                 (Please Print)

and whose Social Security or other Taxpayer Identification Number is:___________

the foregoing Warrant and all rights thereunder, hereby constituting and
appointing ______________________________________ to transfer said Warrant on
the books of the Company, will full power of substitution in the premises.

Dated: ______________, 19__.

                                        Holder's Signature:_____________________

                                        Holder's Name:__________________________
                                                            (Please Print)

                                        Holder's Address:_______________________
                                                            (Please Print)

                                        ________________________________________


Signature Guaranteed: ____________________________________________


NOTE: The signature to this Assignment Form must correspond with the name as it
appears on the face of the Warrant, without alteration or enlargement or any
change whatever, and must be guaranteed by a bank or trust company or by a
member of the National Association of Securities Dealers, Inc. Officers of
corporations and those acting in a fiduciary or other representative capacity
should file proper evidence of authority to assign the foregoing Warrant.

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                              NOTICE OF EXERCISE
                              ------------------

To:  CarsDirect.com, Inc.
     10567 Jefferson Blvdd.
     Culver City, CA 90232


     (1)  The undersigned hereby elects to purchase ______________ shares of
Series D Preferred Stock (the "Shares") of CarsDirect.com, Inc. pursuant to the
terms of the attached Warrant, and tenders herewith payment of the purchase
price in full, together with all applicable transfer taxes, if any.

     (2)  Please issue a certificate or certificates representing the Shares in
the name of the undersigned or in such other name as is specified below:

                     ____________________________________
                                 (Print Name)

                     ____________________________________
                                (Print Address)

                     ____________________________________



     (3)  The undersigned confirms that the Shares are being acquired for the
account of the undersigned for investment only and not with a view to, or for
resale in connection with, the distribution thereof and that the undersigned has
no present intention of distributing or selling the Shares.

     (4)  The undersigned agrees, in connection with the Company's initial
          underwritten public offering of the Company's securities, (1) not to
          sell, make short sale of, loan, grant any options for the purchase of,
          or otherwise dispose of the securities of the Company which are
          acquired directly from the Company, held by the undersigned (other
          than those securities included in the registration) without the prior
          written consent of the Company or the underwriters managing

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          such initial underwritten public offering of the Company's securities
          for one hundred eighty (180) days from the effective date of such
          registration, and (2) further agrees to execute any agreement
          reflecting (1) above as may be requested by the underwriters at the
          time of the public offering.

________________________________             ___________________________________
(Date)                                       (Signature)


                                             ___________________________________
                                             (Print Name)

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