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                                                                     EXHIBIT 4.2

THESE SECURITIES AND THE SECURITIES ISSUABLE UPON THEIR EXERCISE HAVE NOT BEEN
REGISTERED UNDER THE SECURITIES ACT OF 1933 AND MAY NOT BE TRANSFERRED UNLESS
COVERED BY AN EFFECTIVE REGISTRATION STATEMENT UNDER SAID ACT, A "NO ACTION"
LETTER FROM THE SECURITIES AND EXCHANGE COMMISSION WITH RESPECT TO SUCH
TRANSFER, A TRANSFER MEETING THE REQUIREMENTS OF RULE 144 OF THE SECURITIES AND
EXCHANGE COMMISSION, OR AN OPINION OF COUNSEL SATISFACTORY TO THE ISSUER TO THE
EFFECT THAT ANY SUCH TRANSFER IS EXEMPT FROM SUCH REGISTRATION.

                                  SHOPPING.COM

                         COMMON STOCK PURCHASE WARRANT

          1.   Issuance; Certain Definitions.  In consideration of good and
               -----------------------------                               
valuable consideration, the receipt of which is hereby acknowledged by
SHOPPING.COM a Delaware corporation (the "Company"), _______________ or
registered assigns (the "Holder") is hereby granted the right to purchase at any
time until 5:00 P.M., New York City time, on December ____, 2001, Five Hundred
Thousand (500,000) fully paid and nonassessable shares of the Company's Common
Stock, par value $.001 per share (the "Common Stock") at an initial exercise
price per share (the "Exercise Price") of $7.00 per share, subject to further
adjustment as set forth in Section 6 hereof.

          2.   Exercise of Warrants.  This Warrant is exercisable in whole or in
               --------------------                                             
part at the Exercise Price per share of Common Stock payable hereunder, payable
in cash or by certified or official bank check, or by "cashless exercise," by
means of tendering this Warrant Certificate to the Company to receive a number
of shares of Common Stock equal in Market Value to the difference between the
Market Value of the shares of Common Stock issuable upon exercise of this
Warrant and the total cash exercise price thereof.  Upon surrender of this
Warrant Certificate with the annexed Notice of Exercise Form duly executed
(which Notice of Exercise Form may be submitted either by delivery to the
Company or by facsimile transmission as provided in Section 8 hereof), together
with payment of the Exercise Price for the shares of Common Stock purchased, the
Holder shall be entitled to receive a certificate or certificates for the shares
of Common Stock so purchased.  For the purposes of this Section 2, "Market
Value" shall be an amount equal to the average closing bid price of a share of
Common Stock, as reported by Bloomberg, LP or, if not so reported, as reported
on the over-the-counter market for the five (5) trading days preceding the
Company's receipt of the Notice of Exercise Form duly executed multiplied by the
number of shares of Common Stock to be issued upon surrender of this Warrant
Certificate.

                                      -1-
<PAGE>
 
          3.   Reservation of Shares.  The Company hereby agrees that at all
               ---------------------                                        
times during the term of this Warrant there shall be reserved for issuance upon
exercise of this Warrant such number of shares of its Common Stock as shall be
required for issuance upon exercise of this Warrant (the "Warrant Shares").

          4.   Mutilation or Loss of Warrant.  Upon receipt by the Company of
               -----------------------------                                 
evidence satisfactory to it of the loss, theft, destruction or mutilation of
this Warrant, and (in the case of loss, theft or destruction) receipt of
reasonably satisfactory indemnification, and (in the case of mutilation) upon
surrender and cancellation of this Warrant, the Company will execute and deliver
a new Warrant of like tenor and date and any such lost, stolen, destroyed or
mutilated Warrant shall thereupon become void.

          5.   Rights of the Holder.  The Holder shall not, by virtue hereof, be
               --------------------                                             
entitled to any rights of a stockholder in the Company, either at law or equity,
and the rights of the Holder are limited to those expressed in this Warrant and
are not enforceable against the Company except to the extent set forth herein.

          6.   Protection Against Dilution.
               --------------------------- 

               6.1  Adjustment Mechanism.  If an adjustment of the Exercise
                    --------------------                                   
Price is required pursuant to this Section 6, the Holder shall be entitled to
purchase such number of additional shares of Common Stock as will cause (i) the
total number of shares of Common Stock Holder is entitled to purchase pursuant
to this Warrant, multiplied by (ii) the adjusted purchase price per share, to
equal (iii) the dollar amount of the total number of shares of Common Stock
Holder is entitled to purchase before adjustment multiplied by the total
purchase price before adjustment.

               6.2  Capital Adjustments.  In case of any stock split or reverse
                    -------------------                                        
stock split, stock dividend, reclassification of the Common Stock,
recapitalization, merger or consolidation, or like capital adjustment affecting
the Common Stock of the Company, the provisions of this Section 6 shall be
applied as if such capital adjustment event had occurred immediately prior to
the date of this Warrant and the original purchase price had been fairly
allocated to the stock resulting from such capital adjustment; and in other
respects the provisions of this Section shall be applied in a fair, equitable
and reasonable manner so as to give effect, as nearly as may be, to the purposes
hereof.  A rights offering to stockholders shall be deemed a stock dividend to
the extent of the bargain purchase element of the rights.

               6.3  Adjustment for Spin Off.  If, for any reason, prior to the
                    ------------------------                                  
exercise of this Warrant in full, the Company spins off or otherwise divests
itself of a part of its business or operations or disposes all or of a part of
its assets in a transaction (the "Spin Off") in which the Company does not
receive compensation for such business, 

                                      -2-
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operations or assets, but causes securities of another entity (the "Spin Off
Securities") to be issued to security holders of the Company, then

          (a)  the Company shall cause (i) to be reserved Spin Off Securities
     equal to the number thereof which would have been issued to the Holder had
     all of the Holder's unexercised Warrants outstanding on the record date
     (the "Record Date") for determining the amount and number of Spin Off
     Securities to be issued to security holders of the Company (the
     "Outstanding Warrants") been exercised as of the close of business on the
     trading day immediately before the Record Date (the "Reserved Spin Off
     Shares"), and (ii) to be issued to the Holder on the exercise of all or any
     of the Outstanding Warrants, such amount of the Reserved Spin Off Shares
     equal to (x) the Reserved Spin Off Shares multiplied by (y) a fraction, of
     which (I) the numerator is the amount of the Outstanding Warrants then
     being exercised, and (II) the denominator is the amount of the Outstanding
     Warrants; and

          (b) the Exercise Price on the Outstanding Warrants shall be adjusted
     immediately after consummation of the Spin Off by multiplying the Exercise
     Price by a fraction (if, but only if, such fraction is less than 1.0), the
     numerator of which is the Average Market Price of the Common Stock for the
     five (5) trading days immediately following the fifth trading day after the
     Record Date, and the denominator of which is the Average Market Price of
     the Common Stock on the five (5) trading days immediately preceding the
     Record Date; and such adjusted Exercise Price shall be deemed to be the
     Exercise Price with respect to the Outstanding Warrants after the Record
     Date.

For the purposes of this Section 6.3, the "Average Market Price of the Common
Stock" shall mean, for the relevant period, (x) the average closing bid price of
a share of Common Stock, as reported by Bloomberg, LP  or, if not so reported,
as reported on the over-the-counter market or (y) if the Common Stock is listed
on a stock exchange, the closing price on such exchange on the date indicated in
the relevant provision hereof, as reported in The Wall Street Journal.
 
          7.  Transfer to Comply with the Securities Act; Registration Rights.
              --------------------------------------------------------------- 

          (a) This Warrant has not been registered under the Securities Act of
1933, as amended, (the "Act") and has been issued to the Holder for investment
and not with a view to the distribution of either the Warrant or the Warrant
Shares.  Neither this Warrant nor any of the Warrant Shares or any other
security issued or issuable upon exercise of this Warrant may be sold,
transferred, pledged or hypothecated in the absence of an effective registration
statement under the Act relating to such security or an opinion of counsel
satisfactory to the Company that registration is not required under the Act.

                                      -3-
<PAGE>
 
Each certificate for the Warrant, the Warrant Shares and any other security
issued or issuable upon exercise of this Warrant shall contain a legend on the
face thereof, in form and substance satisfactory to counsel for the Company,
setting forth the restrictions on transfer contained in this Section.

          (b)  The Company hereby grants to the Holder piggyback registration
rights with respect to the Warrant Shares.  In the event the Company is filing a
Registration Statement for itself or on behalf of any of its shareholders, the
Company shall notify the Holder in writing reasonably in advance of such filing
(but at least five business days) and give the Holder the opportunity to include
all or any party of the Warrant Shares (whether or not previously issued, to the
extent permissible under the Act or any regulation promulgated thereunder.  Upon
the Holder's notification that the Holder desires to have all or any portion of
the Warrant Shares included in such registration, the Company shall, at no cost
or expense to the Holder, include or cause to be included in such registration
statement the Warrant Shares so identified by the Holder.

          8.   Notices.  Any notice or other communication required or permitted
               -------                                                          
hereunder shall be in writing and shall be delivered personally, telegraphed,
telexed, sent by facsimile transmission or sent by certified, registered or
express mail, postage pre-paid. Any such notice shall be deemed given when so
delivered personally, telegraphed, telexed or sent by facsimile transmission,
or, if mailed, two days after the date of deposit in the United States mails, as
follows:

               (i)  if the to Company, to:

                    SHOPPING.COM
                    2101 East Coast Highway
                    Garden Level
                    Corona del Mar, CA 92625
                    ATTN: Frank Denny
                    Telephone No.: (949) 640-4393
                    Telecopier No.: (949) 640-4374
 
               (ii) if to the Holder, to:
 
                    _______________________________ 
                    _______________________________ 
                    _______________________________ 
                    _______________________________ 
                    _______________________________ 
                    _______________________________ 
 

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                    with a copy to:

                    Krieger & Prager, Esqs.
                    319 Fifth Avenue
                    New York, NY 10016
                    Attn:  Samuel M. Krieger, Esq.
                    Telephone:  (212) 689-3322
                    Telecopier: (212) 213-2077
 
Any party may be notice given in accordance with this Section to the other
parties designate another address or person for receipt of notices hereunder.

          9.   Supplements and Amendments; Whole Agreement.  This Warrant may be
               -------------------------------------------                      
amended or supplemented only by an instrument in writing signed by the parties
hereto.  This Warrant of even date herewith contain the full understanding of
the parties hereto with respect to the subject matter hereof and thereof and
there are no representations, warranties, agreements or understandings other
than expressly contained herein and therein.

          10.  Governing Law.  This Warrant shall be deemed to be a contract
               -------------                                                
made under the laws of the State of New York and for all purposes shall be
governed by and construed in accordance with the laws of such State applicable
to contracts to be made and performed entirely within such State.

          11.  Counterparts.  This Warrant may be executed in any number of
               ------------                                                
counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

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          12.  Descriptive Headings.  Descriptive headings of the several
               --------------------                                      
Sections of this Warrant are inserted for convenience only and shall not control
or affect the meaning or construction of any of the provisions hereof.

     IN WITNESS WHEREOF, the parties hereto have executed this Warrant as of the
7th day of December, 1998.


                              SHOPPING.COM


                              By:    /s/ Kristine Webster
                                    -------------------------------------
                                    Name:  Kristine E. Webster
                                    Its:   CFO

Attest:


________________________
Name:
Title:

                                      -6-
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                         NOTICE OF EXERCISE OF WARRANT

     The undersigned hereby irrevocably elects to exercise the right,
represented by the Warrant Certificate dated as of ___________________, 1998, to
purchase ________ shares of the Common Stock, par value $.001 per share, of
SHOPPING.COM and tenders herewith payment in accordance with Section 1 of said
Common Stock Purchase Warrant.

     Please deliver the stock certificate to:

 



Dated:______________________



____________________________
[Name of Holder]



By:_______________________________________________



[_]  CASH:     $ _______________________


[_]  CASHLESS EXERCISE

                                      -7-