<PAGE>

                                                                     Exhibit 4.1

THIS WARRANT AND THE SHARES OF CAPITAL STOCK ISSUED UPON ANY EXERCISE HEREOF
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"SECURITIES ACT"), OR ANY APPLICABLE STATE SECURITIES OR "BLUE-SKY" LAWS AND MAY
NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF
IN THE ABSENCE OF SUCH REGISTRATION OR AN EXEMPTION THEREFROM. ADDITIONALLY, THE
TRANSFER OF THIS WARRANT AND THE SHARES OF CAPITAL STOCK ISSUED UPON ANY
EXERCISE HEREOF IS SUBJECT TO THE CONDITIONS SPECIFIED IN SECTION 6.2 OF THE
ASSET PURCHASE AGREEMENT DATED AS OF NOVEMBER 26, 2001 BETWEEN ALLOY, INC.,
ALLOY ACQUISITION SUB, INC. AND MARKETSOURCE CORPORATION (THE "PURCHASE
AGREEMENT") AND NO TRANSFER OF ANY SUCH SECURITIES SHALL BE VALID OR EFFECTIVE
UNTIL SUCH CONDITIONS HAVE BEEN FULFILLED. UPON THE FULFILLMENT OF CERTAIN OF
SUCH CONDITIONS, ALLOY, INC. HAS AGREED TO DELIVER TO THE HOLDER HEREOF A
CERTIFICATE, NOT BEARING THIS LEGEND, FOR THE SECURITIES REPRESENTED HEREBY
REGISTERED IN THE NAME OF THE HOLDER HEREOF. COPIES OF SUCH AGREEMENT MAY BE
OBTAINED AT NO COST BY WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THIS
CERTIFICATE TO THE SECRETARY OF ALLOY, INC.

No. MS-001                                                      For the Purchase
                                                               of 100,000 shares
                                                                 of Common Stock

                        WARRANT TO PURCHASE COMMON STOCK

                                       OF

                                  ALLOY, INC.

                            (A DELAWARE CORPORATION)

     ALLOY, INC., a Delaware corporation (the "Company"), for value received,
hereby certifies that MarketSource Corporation (the "Holder"), is entitled,
subject to the terms set forth below, to purchase from the Company, at any time
or from time to time following the Applicable Exercise Eligibility Date (as
defined below) and before the earlier of 5:00 p.m. Eastern Standard Time on the
Applicable Expiration Date and the termination of this Warrant as provided in
Section 8 hereof, up to an aggregate of 100,000 shares of Common Stock, par
value $0.01 per share, of the Company (the "Common Stock"), at a purchase price
equal to $13.78 per share, as may be adjusted upon the occurrence of certain
events as set forth in Section 3 of this Warrant. The shares of stock issuable
upon exercise of this Warrant, and the purchase price per share, are hereinafter
referred to as the "Warrant Stock" and the "Purchase Price," respectively. For
purposes hereof, the term "Applicable Exercise Eligibility Date" means, with
respect to fifty percent (50%) of the shares of Common Stock for which this
Warrant may be exercised, November 26, 2002, and, with respect to
<PAGE>

the remaining shares for which this Warrant may be exercised, November 26, 2003;
provided, however, that in the event that a merger or consolidation of the
--------  -------
Company into another corporation (other than a merger or reorganization
involving only a change in the state of incorporation of the Company or the
acquisition by the Company of other businesses where the Company survives as a
going concern), or the sale of all or substantially all of the Company's capital
stock or assets to any other person, is consummated, the "Applicable Exercise
Eligibility Date" shall mean, with respect to all of the shares of Common Stock
for which this Warrant may be exercised which have not yet become exercisable
hereunder, the effective date of such merger, consolidation or sale. For
purposes hereof, the term "Applicable Expiration Date" means, with respect to
the shares of Common Stock that become eligible for purchase on November 26,
2002, November 25, 2007, and, with respect to the shares of Common Stock that
become eligible for purchase on November 26, 2003, November 25, 2008.

     1.   Exercise.
          --------

          1.1  Manner of Exercise; Payment in Cash.  This Warrant may be
               -----------------------------------
     exercised by the Holder, in whole or in part, by surrendering this Warrant,
     with the purchase form appended hereto as Exhibit A duly executed by the
                                               ---------
     Holder, at the principal office of the Company, or at such other place as
     the Company may designate, accompanied by payment in full of the Purchase
     Price payable in respect of the number of shares of Warrant Stock purchased
     upon such exercise. Payment of the Purchase Price shall be in cash or by
     certified or official bank check payable to the order of the Company.

          1.2  Effectiveness.  Each exercise of this Warrant shall be deemed to
               -------------
     have been effected immediately prior to the close of business on the day on
     which this Warrant shall have been surrendered to the Company as provided
     in Section 1.1 above. At such time, the person or persons in whose name or
     names any certificates for Warrant Stock shall be issuable upon such
     exercise as provided in Section 1.3 below shall be deemed to have become
     the holder or holders of record of the Warrant Stock represented by such
     certificates.

          1.3  Delivery of Certificates.  As soon as practicable after the
               ------------------------
     exercise of this Warrant in whole or in part, and in any event within
     twenty (20) days thereafter, the Company at its sole expense will cause to
     be issued in the name of, and delivered to, the Holder, or, subject to the
     terms and conditions hereof, as such Holder (upon payment by such Holder of
     any applicable transfer taxes) may direct:

               (a) a certificate or certificates for the number of full shares
          of Warrant Stock to which such Holder shall be entitled upon such
          exercise plus, in lieu of any fractional share to which such Holder
          would otherwise be entitled, cash in an amount determined pursuant to
          Section 2 hereof, and

               (b) if such exercise is in part only, a new warrant or warrants
          (dated the date hereof) of like tenor, calling in the aggregate on the
          face or faces thereof for the number of shares of Warrant Stock
          (without giving effect to any adjustment therein) equal to the number
          of such shares called for on the face of this Warrant minus the

                                      -2-
<PAGE>

          number of such shares purchased by the Holder upon such exercise as
          provided in Section 1.1 above.

     2.   Fractional Shares.  The Company shall not be required upon the
          -----------------
exercise of this Warrant to issue any fractional shares, but shall make an
adjustment therefor in cash on the basis of the fair market value of the Warrant
Stock reasonably determined by the Board of Directors of the Company.

     3.   Certain Adjustments.
          -------------------

          3.1  Changes in Common Stock.  If the Company shall (i) combine the
               -----------------------
     outstanding shares of Common Stock into a lesser number of shares, (ii)
     subdivide the outstanding shares of Common Stock into a greater number of
     shares or (iii) issue additional shares of Common Stock as a dividend or
     other distribution with respect to the Common Stock, the number of shares
     of Warrant Stock shall be equal to the number of shares which the Holder
     would have been entitled to receive after the happening of any of the
     events described above if such shares had been issued immediately prior to
     the happening of such event, such adjustment to become effective
     concurrently with the effectiveness of such event. The Purchase Price in
     effect immediately prior to any such combination of Common Stock shall,
     upon the effectiveness of such combination, be proportionately increased.
     The Purchase Price in effect immediately prior to any such subdivision of
     Common Stock or at the record date of such dividend shall upon the
     effectiveness of such subdivision or immediately after the record date of
     such dividend be proportionately reduced.

          3.2  Reorganizations and Reclassifications.  If there shall occur any
               -------------------------------------
     capital reorganization or reclassification of the Common Stock (other than
     a change in par value or a subdivision or combination as provided for in
     Section 3.1), then, as part of any such reorganization or reclassification,
     lawful provision shall be made so that the Holder shall have the right
     thereafter to receive upon the exercise hereof the kind and amount of
     shares of stock or other securities or property which such Holder would
     have been entitled to receive if, immediately prior to any such
     reorganization or reclassification, such Holder had held the number of
     shares of Common Stock which were then purchasable upon the exercise of
     this Warrant. In any such case, appropriate adjustment (as reasonably
     determined by the Board of Directors of the Company) shall be made in the
     application of the provisions set forth herein with respect to the rights
     and interests thereafter of the Holder such that the provisions set forth
     in this Section 3 (including provisions with respect to adjustment of the
     Purchase Price) shall thereafter be applicable, as nearly as is reasonably
     practicable, in relation to any shares of stock or other securities or
     property thereafter deliverable upon the exercise of this Warrant.

          3.3  Merger, Consolidation or Sale of Assets. Subject to the
               ---------------------------------------
     provisions of Section 8, if there shall be a merger or consolidation of the
     Company with or into another corporation (other than a merger or
     reorganization involving only a change in the state of incorporation of the
     Company or the acquisition by the Company of other businesses where the
     Company survives as a going concern), or the sale of all or substantially
     all of the Company's capital stock or assets to any other person, then as a
     part of such transaction, provision shall be made so that the Holder shall
     thereafter be entitled to receive the number

                                      -3-
<PAGE>

     of shares of stock or other securities or property of the Company, or of
     the successor corporation resulting from the merger, consolidation or sale,
     to which the Holder would have been entitled if the Holder had exercised
     its rights pursuant to the Warrant immediately prior thereto. In any such
     case, appropriate adjustment shall be made in the application of the
     provisions of this Section 3 to the end that the provisions of this Section
     3 shall be applicable after that event in as nearly equivalent a manner as
     may be practicable.

          3.4  Certificate of Adjustment.  When any adjustment is required to be
               -------------------------
     made in the Purchase Price, the Company shall mail to the Holder a
     certificate setting forth the Purchase Price after such adjustment and
     setting forth a brief statement of the facts requiring such adjustment.
     Delivery of such certificate shall be deemed to be a final and binding
     determination with respect to such adjustment unless challenged by the
     Holder within twenty (20) days of receipt thereof. Such certificate shall
     also set forth the kind and amount of stock or other securities or property
     into which this Warrant shall be exercisable following the occurrence of
     any of the events specified in this Section 3.

     4.   Compliance with Securities Act.
          ------------------------------

          4.1  Unregistered Securities.  The Holder acknowledges that this
               -----------------------
     Warrant and the Warrant Stock have not been registered under the Securities
     Act of 1933, as amended, and the rules and regulations thereunder, or any
     successor legislation (the "Securities Act"), and agrees not to sell,
     pledge, distribute, offer for sale, transfer or otherwise dispose of this
     Warrant or any Warrant Stock except in accordance with the provisions of
     Section 6.2 of the Purchase Agreement, which provisions are hereby
     incorporated by reference herein.

          4.2  Investment Letter.  Without limiting the generality of Section
               -----------------
     4.1, unless the offer and sale of any shares of Warrant Stock shall have
     been effectively registered under the Securities Act, the Company shall be
     under no obligation to issue the Warrant Stock unless and until the Holder
     shall have executed an investment letter in form and substance satisfactory
     to the Company, including a warranty at the time of such exercise that the
     Holder is acquiring such shares for its own account, for investment and not
     with a view to, or for sale in connection with, the distribution of any
     such shares.

          4.3  Legend.  Certificates delivered to the Holder pursuant to Section
               ------
     1.3 shall bear the following legend or a legend in substantially similar
     form:

          "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR
          INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF
          1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES OR "BLUE-SKY"
          LAWS. THESE SECURITIES MAY NOT BE SOLD, TRANSFERRED, ASSIGNED,
          PLEDGED, ENCUMBERED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH
          REGISTRATION OR AN EXEMPTION THEREFROM. ADDITIONALLY, THE TRANSFER OF
          THESE SECURITIES IS SUBJECT TO THE CONDITIONS SPECIFIED IN SECTION 6.2
          OF THE ASSET PURCHASE AGREEMENT DATED AS OF NOVEMBER

                                      -4-
<PAGE>

          26, 2001 BETWEEN ALLOY, INC., ALLOY ACQUISITION SUB, INC. AND
          MARKETSOURCE CORPORATION AND NO TRANSFER OF THESE SECURITIES SHALL BE
          VALID OR EFFECTIVE UNTIL SUCH CONDITIONS HAVE BEEN FULFILLED. UPON THE
          FULFILLMENT OF CERTAIN OF SUCH CONDITIONS, ALLOY, INC. HAS AGREED TO
          DELIVER TO THE HOLDER HEREOF A CERTIFICATE, NOT BEARING THIS LEGEND,
          FOR THE SECURITIES REPRESENTED HEREBY REGISTERED IN THE NAME OF THE
          HOLDER HEREOF. COPIES OF SUCH AGREEMENT MAY BE OBTAINED AT NO COST BY
          WRITTEN REQUEST MADE BY THE HOLDER OF RECORD OF THIS CERTIFICATE TO
          THE SECRETARY OF ALLOY, INC."

     5.   Reservation of Stock.  The Company will at all times reserve and keep
          --------------------
available, solely for issuance and delivery upon the exercise of this Warrant,
such shares of Warrant Stock and other stock, securities and property, as from
time to time shall be issuable upon the exercise of this Warrant. The Company
covenants that all shares of Warrant Stock so issuable will, when issued, be
duly and validly issued and fully paid and nonassessable.

     6.   [Reserved.]
           --------

     7.   Replacement of Warrants.  Upon receipt of evidence reasonably
          -----------------------
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and (in the case of loss, theft or destruction) upon delivery of an
indemnity agreement (with surety if reasonably required) in an amount reasonably
satisfactory to the Company, or (in the case of mutilation) upon surrender and
cancellation of this Warrant, the Company will issue, in lieu thereof, a new
Warrant of like tenor.

     8.   Termination Upon Certain Events.   If there shall be a merger or
          -------------------------------
consolidation of the Company with or into another corporation (other than a
merger or reorganization involving only a change in the state of incorporation
of the Company or the acquisition by the Company of other businesses where the
Company survives as a going concern), or the sale of all or substantially all of
the Company's capital stock or assets to any other person, or the liquidation or
dissolution of the Company, then as a part of such transaction, at the Company's
option, either:

          (a) provision shall be made so that the Holder shall thereafter be
     entitled to receive the number of shares of stock or other securities or
     property of the Company, or of the successor corporation resulting from the
     merger, consolidation or sale, to which the Holder would have been entitled
     if the Holder had exercised its rights pursuant to the Warrant immediately
     prior thereto (and, in such case, appropriate adjustment shall be made in
     the application of the provisions of this Section 8(a) to the end that the
     provisions of this Section 3 shall be applicable after that event in as
     nearly equivalent a manner as may be practicable); or

          (b) this Warrant shall terminate on the effective date of such merger,
     consolidation or sale (the "Termination Date") and become null and void,
     provided that if this Warrant shall not have otherwise terminated or
     --------
     expired, (1) the Company shall provide the Holder written notice of such
     Termination Date at least twenty (20) days prior to the

                                      -5-
<PAGE>

     occurrence thereof and (2) the Holder shall have the right until 5:00 p.m.,
     Eastern Standard Time, on the day immediately prior to the Termination Date
     to exercise its rights hereunder to the extent not previously exercised.

     9.   Transferability.  Without the prior written consent of the Company,
          ---------------
this Warrant shall not be assigned, pledged or hypothecated in any way (whether
by operation of law or otherwise) and shall not be subject to execution,
attachment or similar process; provided that, this Warrant may be transferred by
                               -------- ----
the Holder as a dividend, distribution upon liquidation of the Holder or bona
fide gift without consideration. Any attempted transfer, assignment, pledge,
hypothecation or other disposition of the Warrant or of any rights granted
hereunder contrary to the provisions of this Section 9, or the levy of any
attachment or similar process upon the Warrant or such rights, shall be null and
void.

     10.  No Rights as Stockholder.  Until the exercise of this Warrant, the
          ------------------------
Holder shall not have or exercise any rights by virtue hereof as a stockholder
of the Company.

     11.  Notices.  All notices, requests and other communications hereunder
          -------
shall be in writing, shall be either (i) delivered by hand, (ii) made by
facsimile transmission, (iii) sent by overnight courier, or (iv) sent by
registered mail, postage prepaid, return receipt requested. In the case of
notices from the Company to the Holder, they shall be sent to the address
furnished to the Company in writing by the last Holder who shall have furnished
an address to the Company in writing. All notices from the Holder to the Company
shall be delivered to the Company at its offices at 151 West 26th Street,
11th Floor, New York, New York 10001, Attn: Chief Executive Officer or such
other address as the Company shall so notify the Holder. All notices, requests
and other communications hereunder shall be deemed to have been given (i) by
hand, at the time of the delivery thereof to the receiving party at the address
of such party described above, (ii) if made by facsimile transmission, at the
time that receipt thereof has been acknowledged by electronic confirmation or
otherwise, (iii) if sent by overnight courier, on the next business day
following the day such notice is delivered to the courier service, or (iv) if
sent by registered mail, on the fifth business day following the day such
mailing is made.

     12.  Waivers and Modifications. Any term or provision of this Warrant may
          -------------------------
be waived only by written document executed by the party entitled to the
benefits of such terms or provisions. The terms and provisions of this Warrant
may be modified or amended only by written agreement executed by the parties
hereto.

     12.  Headings.  The headings in this Warrant are for convenience of
          --------
reference only and shall in no way modify or affect the meaning or construction
of any of the terms or provisions of this Warrant.

     14.  Governing Law.  This Warrant will be governed by and construed in
          -------------
accordance with and governed by the laws of Delaware, without giving effect to
the conflict of law principles thereof.

                  [Remainder of Page Intentionally Left Blank]

                                      -6-
<PAGE>

     IN WITNESS WHEREOF, this Warrant has be executed by the undersigned as of
this 26th day of November, 2001


                                     ALLOY, INC.


                                     By: /s/ Gina R. DiGioia
                                        -------------------------------
                                     Name:  Gina R. DiGioia
                                          -----------------------------
                                     Title: VP / General Counsel
                                           ----------------------------





                   [Signature Page to Warrant - MarketSource]

                                      -7-
<PAGE>

                                    EXHIBIT A
                                    ---------

                                  PURCHASE FORM
                                  -------------

To:  ALLOY, INC.

     The undersigned, pursuant to the provisions set forth in the attached
Warrant (No. ____), hereby irrevocably elects to purchase ________ shares of the
Common Stock, par value $0.01 per share (the "Common Stock") of ALLOY, INC.,
covered by such Warrant and herewith makes payment of $__________, representing
the full purchase price for such shares at the price per share provided for in
such Warrant. The Common Stock for which the Warrant may be exercised shall be
known herein as the "Warrant Stock".

     The undersigned is aware that the Warrant Stock has not been and will not
be registered under the Securities Act of 1933, as amended (the "Securities
Act") or any state securities laws. The undersigned understands that reliance by
the Company on exemptions under the Securities Act is predicated in part upon
the truth and accuracy of the statements of the undersigned in this Purchase
Form.

     The undersigned represents and warrants that (1) it has been furnished with
all information which it deems necessary to evaluate the merits and risks of the
purchase of the Warrant Stock, (2) it has had the opportunity to ask questions
concerning the Warrant Stock and the Company and all questions posed have been
answered to its satisfaction, (3) it has been given the opportunity to obtain
any additional information it deems necessary to verify the accuracy of any
information obtained concerning the Warrant Stock and the Company and (4) it has
such knowledge and experience in financial and business matters that it is able
to evaluate the merits and risks of purchasing the Warrant Stock and to make an
informed investment decision relating thereto.

     The undersigned hereby represents and warrant that it is purchasing the
Warrant Stock for its own account for investment and not with a view to the sale
or distribution of all or any part of the Warrant Stock.

     The undersigned understands that because the Warrant Stock has not been
registered under the Securities Act, it must continue to bear the economic risk
of the investment for an indefinite period of time and the Warrant Stock cannot
be sold unless it is subsequently registered under applicable federal and state
securities laws or an exemption from such registration is available.

     The undersigned agrees that it will in no event sell or distribute or
otherwise dispose of all or any part of the Warrant Stock unless (1) there is an
effective registration statement under the Securities Act and applicable state
securities laws covering any such transaction involving the Warrant Stock, or
(2) the Company receives an opinion satisfactory to the Company of the
undersigned's legal counsel stating that such transaction is exempt from
registration. The undersigned consents to the placing of a legend on its
certificate for the Warrant Stock stating that the Warrant Stock has not been
registered and setting forth the restriction on transfer
<PAGE>

contemplated hereby and to the placing of a stop transfer order on the books of
the Company and with any transfer agents against the Warrant Stock until the
Warrant Stock may be legally resold or distributed without restriction.

     The undersigned has considered the federal and state income tax
implications of the exercise of the Warrant and the purchase and subsequent sale
of the Warrant Stock.



                                     _______________________________

                                     Dated:_________________________


                                      -2-