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                                                                   EXHIBIT 10.19

                     SECURED, NON-RECOURSE PROMISSORY NOTE
                                   NEGOTIABLE

US$69,735.00                                                      March 23, 2000
                                                           San Diego, California

FOR VALUE RECEIVED, the undersigned ("Maker") promises to pay to the order of
WebSideStory, Inc., a corporation organized under the laws of the state of
California ("Holder"), at 10182 Telesis Court, San Diego, California or at such
other place as the Holder hereof may from time to time designate, the principal
sum of SIXTY-NINE THOUSAND SEVEN HUNDRED THIRTY-FIVE dollars ($69,735.00), with
interest on the unpaid principal balance from time to time outstanding, computed
on the basis of a three hundred sixty (360) day year, actual days elapsed, at a
rate (the "Interest Rate") equal to 6.5% per annum. Payment of principal and
interest shall be made in the lawful money of the United States which shall be
legal tender for public and private debts at the time of payment. The entire
outstanding principal balance and all accrued but unpaid interest shall be due
and payable on the third anniversary of this note (the "Due Date"). Each payment
hereunder shall be credited first to interest then accrued and the remainder to
unpaid principal, and interest shall thereupon cease upon the principal so
credited. Maker shall have the right to repay all or a portion of the
outstanding principal and/or interest hereunder at any time or times prior to
the Due Date, without penalty.

This note shall automatically become due and payable prior to the Due Date,
without notice or demand and without the need for any action or election by the
Holder hereof, upon the occurrence at any time of any of the following events of
default:

        (1) The making of an assignment for the benefit of creditors by any
party liable for the payment of this note, whether as maker, endorser,
guarantor, surety, or otherwise, or the voluntary appointment (at the request of
any such party or with the consent of any such party) of a receiver, custodian,
liquidator or trustee in bankruptcy of any such party's property or the filing
by any such party of a petition in bankruptcy or other similar proceeding under
law for relief of debtors; or

        (2) The filing (other than by Holder) against any party liable for the
payment of this note, whether as maker, endorser, surety, or otherwise, of a
petition in bankruptcy or other similar proceeding under law for relief of
debtors, or the involuntary appointment of a receiver, custodian, liquidator or
trustee in bankruptcy of the property of any such party, and such petition or
appointment is not vacated or discharged within ninety (90) calendar days after
the filing or making thereof.

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If this note is not paid when due, whether at the Due Date or by acceleration,
the undersigned promises to pay all costs of collection, including without
limitation reasonable attorneys' fees, and all expenses in connection with the
protection or realization of any collateral securing this note incurred by the
Holder hereof on account of such collection, whether or not suit is filed
hereon; such costs and expenses shall include without limitation all costs,
attorneys' fees and expenses incurred by the Holder hereof in connection with
any insolvency, bankruptcy, reorganization, arrangement or other similar
proceedings involving the undersigned or involving any endorser hereof, which in
any way affect the exercise by the Holder hereof of its rights and remedies
under this note or under any security agreement, pledge agreement, cash
collateral agreement or other agreement securing this note.

Presentment, demand, protest, notices of protest, dishonor and non-payment of
this note and all notices of every kind are hereby waived. To the extent
permitted by applicable law, the defense of the statute of limitations is hereby
waived by the undersigned.

This note is secured by a stock pledge (the "Stock Pledge") of even date
herewith pursuant to which a first priority security interest has been granted
to Holder by Maker in 3,179,171 shares of common stock of Holder. Upon the
occurrence of any event of default under this note, Holder shall be entitled to
exercise its rights under the Stock Pledge, including the exercise of any and
all rights and remedies available to Holder as a secured party under the
California Uniform Commercial Code or other applicable law, including the right
to sell the pledged stock in a public or private sale (in accordance with the
California Uniform Commercial Code) and the right to accept the pledged stock in
discharge of Maker's obligations hereunder. In the event of any recapitalization
of Holder, Holder's security interest shall automatically attach to the shares
into which the pledged stock shall have been converted. If Maker fails to make a
payment due under this note, Holder's only recourse will be against any
collateral securing the obligations represented by this note, including shares
pledged pursuant to the Stock Pledge, and Holder will have no recourse against
other assets of Maker.

No single or partial exercise of any power hereunder or under any security
agreement, pledge agreement, cash collateral agreement or other agreement
securing this note shall preclude other or further exercise thereof or the
exercise of any other power. The Holder hereof shall at all times have the right
to proceed against any portion of the security held for this note in such order
and in such manner as the Holder may deem fit, without waiving any rights with
respect to any other security. No delay or omission on the part of the Holder
hereof in exercising any right hereunder shall operate as a waiver of such right
or of any other right under this note. The release of any party liable on this
note shall not operate to release any other party liable hereon.

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This note may be prepaid in whole or in part at any time without premium or
penalty. Partial prepayments of principal shall not postpone or delay the date
of any subsequent payments of principal or change the amount of such payments.

The payment obligations of both principal and interest represented by this note
will be forgiven in full, and this note will be returned to Maker promptly, if
and when any of the following events occurs on or before the Due Date:

1    a voluntary sale by Holder's shareholders of a majority of the Holder's
     common stock;

2    a voluntary sale of substantially all assets of Holder;

3    Holder has cash and cash equivalents in aggregate in excess of $4 million;

4    Constructive Termination as defined in the Stock Option Agreement of
     December 20, 1999 between Maker and Holder.

Notwithstanding the fact that Holder has cash and cash equivalents in excess of
$4 million (the "Liquidity Condition"), if Holder is in registration for or
shall have completed an initial public offering of its equity securities prior
to December 31, 2000, forgiveness of such payment obligations shall not be
forgiven upon occurrence of the Liquidity Condition, but rather such obligations
shall be forgiven on a pro-rata basis over twelve months commencing the date
such public offering is completed or January 1, 2001, whichever is earlier.

Any notices required to be given hereunder shall be deemed delivered five (5)
days after such notice in writing is placed in the United States Mail, postage
prepaid to the following addresse(s):

               If to Holder:
               WebSideStory
               10182 Telesis Court
               San Diego, CA 92121

               Attn:  legal department

               If to Maker:
               John Hentrich
               4778 Keswick Court
               San Diego  CA  92130

The term "Holder" shall include all of Holder's successors and assigns to whom
the benefits of this note shall inure.

In the event any provision of this note is held to be invalid, illegal or
otherwise unenforceable in any respect, such provision shall be construed as
containing the

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maximum valid, legal and enforceable terms and conditions, and all other
provisions of this note shall remain in full force and effect to the maximum
extent permitted by law.

Any provision of this note that is prohibited or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability without invalidating the remaining
provisions of this note, and such prohibition or unenforceability in any
jurisdiction shall not invalidate, or render unenforceable such provision in any
other jurisdiction.

This note has been executed and delivered by the undersigned in the State of
California and is to be governed by and construed in accordance with the laws of
the State of California without regard to its conflicts of laws rules. In any
action brought under or arising out of this note, the undersigned hereby
consents to the jurisdiction of any competent court within the State of
California and consents to service of process by any means authorized by the law
of that State. This note may be modified, amended or terminated only by a
writing signed by both the Holder and the Maker.

                                       "MAKER"

                                       /s/ John Hentrich
                                       ------------------------------------
                                       John Hentrich

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                                                                 EXHIBIT 10.20

                             STOCK PLEDGE AGREEMENT

        THIS STOCK PLEDGE AGREEMENT ("Pledge Agreement") is made by JOHN
HENTRICH; an individual ("Pledgor") in favor of WEBSIDESTORY, INC., a California
corporation, located at 10182 Telesis Court, San Diego, California or at such
other place as may be designated from time to time ("Pledgee").

        WHEREAS, Pledgor has concurrently executed that certain Secured,
Non-Recourse Promissory Note (the "Note") in favor of Pledgee in the amount of
sixty-nine thousand seven hundred thirty-five dollars ($69,735); and

        WHEREAS, Pledgee is willing to accept the Note from Pledgor, but only
upon the condition, among others, that Pledgor shall have executed and delivered
to Pledgee this Pledge Agreement and the Collateral (as defined below):

        NOW, THEREFORE, in consideration of the foregoing recitals and for other
good and valuable consideration, the receipt and adequacy of which are hereby
acknowledged, and intending to be legally bound, Pledgor hereby agrees as
follows:

        1. As security for the full, prompt and complete payment and performance
when due (whether by stated maturity, by acceleration or otherwise) of all
indebtedness of Pledgor to Pledgee created under the Note (all such indebtedness
being the "Liabilities"), together with, without limitation, the prompt payment
of all expenses, including, without limitation, reasonable attorneys' fees and
legal expenses, incidental to the collection of the Liabilities and the
enforcement or protection of Pledgee's lien in and to the collateral pledged
hereunder, Pledgor hereby pledges to Pledgee, and grants to Pledgee, a first
priority security interest in all of the following (collectively, the "Pledged
Collateral"):

               (a) Three million one hundred seventy nine thousand one hundred
seventy one (3,179,171) shares of Common Stock of Pledgee represented by
Certificate Number 6 (the "Pledged Shares"), and all dividends, cash,
instruments, and other property or proceeds from time to time received,
receivable, or otherwise distributed in respect of or in exchange for any or all
of the Pledged Shares; and

               (b) all voting trust certificates held by Pledgor evidencing the
right to vote any Pledged Shares subject to any voting trust.

        The term "indebtedness" is used herein in its most comprehensive sense
and includes any and all advances, debts, obligations and Liabilities
heretofore, now or hereafter made, incurred or created, whether voluntary or
involuntary and whether due or not due, absolute or contingent, liquidated or
unliquidated, determined or undetermined, and whether recovery upon such
indebtedness may be or hereafter becomes unenforceable.

        2. At any time, without notice, and at the expense of Pledgor, Pledgee
in its name or in the name of its nominee or of Pledgor may, but shall not be
obligated to: (1) collect by legal proceedings or otherwise all dividends
(except cash dividends other than liquidating dividends), interest, principal
payments and other sums now or hereafter payable upon or on account of said

                                       1.
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Pledged Collateral; (2) enter into any extension, reorganization, deposit,
merger or consolidation agreement, or any agreement in any way relating to or
affecting the Pledged Collateral, and in connection therewith may deposit or
surrender control of such Pledged Collateral thereunder, accept other property
in exchange for such Pledged Collateral and do and perform such acts and things
as it may deem proper, and any money or property received in exchange for such
Pledged Collateral shall be applied to the indebtedness or thereafter held by it
pursuant to the provisions hereof; (3) insure, process and preserve the Pledged
Collateral; (4) cause the Pledged Collateral to be transferred to its name or to
the name of its nominee; and (5) exercise as to such Pledged Collateral all the
rights, powers and remedies of an owner, except that so long as no default
exists under the Note or hereunder Pledgor shall retain all voting rights as to
the Pledged Shares.

        3. Pledgee shall hold as security pursuant to this Pledge Agreement the
certificate or certificates representing the Pledged Shares at its office.
Pledgee shall have no rights to the Pledged Shares except, and then only to the
extent, as may accrue pursuant hereto; and Pledgee shall upon full payment and
performance of the Liabilities and/or the termination of the security interest
created hereby, relinquish said certificate or certificates to Pledgor.

        4. Pledgor agrees to pay prior to delinquency all taxes, charges, liens
and assessments against the Pledged Collateral, and upon the failure of Pledgor
to do so, Pledgee at its option may pay any of them and shall be the sole judge
of the legality or validity thereof and the amount necessary to discharge the
same.

        5. At the option of Pledgee and without necessity of demand or notice,
all or any part of the indebtedness of Pledgor shall immediately become due and
payable irrespective of any agreed maturity, upon the happening of any of the
following events: (1) failure to keep or perform any of the terms or provisions
of this Pledge Agreement; (2) failure to pay any installment of principal or
interest on the Note when due; (3) the levy of any attachment, execution or
other process against the Pledged Collateral; or (4) the insolvency, commission
of an act of bankruptcy, general assignment for the benefit of creditors,
filing of any petition in bankruptcy or for relief under the provisions of Title
11 of the United States Code of, by, or against Pledgor.

        6. In the event of the nonpayment of any indebtedness when due, whether
by acceleration or otherwise, or upon the happening of any of the events
specified in the last preceding paragraph, Pledgee may then, or at any time
thereafter, at its election, apply, set off, collect or sell in one or more
sales, or take such steps as may be necessary to liquidate and reduce to cash in
the hands of Pledgee in whole or in part, with or without any previous demands
or demand of performance or notice or advertisement, the whole or any part of
the Pledged Collateral in such order as Pledgee may elect, and any such sale may
be made either at public or private sale at its place of business or elsewhere,
or at any broker's board or securities exchange, either for cash or upon credit
or for future delivery; provided, however, that if such disposition is at
private sale, then the purchase price of the Pledged Collateral shall be equal
to the public market price then in effect, or, if at the time of sale no public
market for the Pledged Collateral exists, then, in recognition of the fact that
the sale of the Pledged Collateral would have to be registered under the
Securities Act of 1933 and that the expenses of such registration are
commercially unreasonable for the type and amount of collateral pledged
hereunder, Pledgee and Pledgor hereby agree that such private sale shall be at a
purchase price mutually agreed to by

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Pledgee and Pledgor or, if the parties cannot agree upon a purchase price, then
at a purchase price established by a majority of three independent appraisers
knowledgeable of the value of such collateral, one named by Pledgor within 10
days after written request by the Pledgee to do so, one named by Pledgee within
such 10 day period, and the third named by the two appraisers so selected, with
the appraisal to be rendered by such body within 30 days of the appointment of
the third appraiser. The cost of such appraisal, including all appraiser's fees,
shall be charged against the proceeds of sale as an expense of such sale.
Pledgee may be the purchaser of any or all Pledged Collateral so sold and hold
the same thereafter in its own right free from any claim of Pledgor or right of
redemption. Demands of performance, notices of sale, advertisements and presence
of property at sale are hereby waived, and Pledgee is hereby authorized to sell
hereunder any evidence of debt pledged to it. Any sale hereunder may be
conducted by any officer or agent of Pledgee.

        7. The proceeds of the sale of any of the Pledged Collateral and all
sums received or collected by Pledgee from or on account of such Pledged
Collateral shall be applied by Pledgee to the payment of expenses incurred or
paid by Pledgee in connection with any sale, transfer or delivery of the Pledged
Collateral, to the payment of any other costs, charges, attorneys' fees or
expenses mentioned herein, and to the payment of the indebtedness or any part
hereof, all in such order and manner as Pledgee in its discretion may determine.
Pledgee shall then pay any balance to Pledgor.

        8. Upon the transfer of all or any part of the indebtedness Pledgee may
transfer all or any part of the Pledged Collateral and shall be fully discharged
thereafter from all liability and responsibility with respect to such Pledged
Collateral so transferred, and the transferee shall be vested with all the
rights and powers of Pledgee hereunder with respect to such Pledged Collateral
so transferred; but with respect to any Pledged Collateral not so transferred
Pledgee shall retain all rights and powers hereby given.

        9. Until all indebtedness shall have been paid in full the power of sale
and all other rights, powers and remedies granted to Pledgee hereunder shall
continue to exist and may be exercised by Pledgee at any time and from time to
time irrespective of the fact that the indebtedness or any part thereof may have
become barred by any statute of limitations, or that the personal liability of
Pledgor may have ceased.

        10. Pledgee agrees that so long as no default exists under the Note or
hereunder, the Pledged Shares shall, upon the request of Pledgor, be released
from pledge as the indebtedness is paid. In addition, the Pledged Shares shall
be released from pledge as set forth in the Note.

        11. Pledgee may at any time deliver the Pledged Collateral or any part
thereof to Pledgor and the receipt of Pledgor shall be a complete and full
acquittance for the Pledged Collateral so delivered, acrd Pledgee shall
thereafter be discharged from any liability or responsibility therefor.

        12. The rights, powers and remedies given to Pledgee by this Pledge
Agreement shall be in addition to all rights, powers and remedies given to
Pledgee by virtue of any statute or rule of law. Any forbearance or failure or
delay by Pledgee in exercising any right, power or remedy hereunder shall not be
deemed to be a waiver of such right, power or remedy, and any single or

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partial exercise of any right, power or remedy hereunder shall not preclude the
further exercise thereof; and every right, power and remedy of Pledgee shall
continue in full force and effect until such right, power or remedy is
specifically waived by an instrument in writing executed by Pledgee.

        13. If any provision of this Pledge Agreement is held to be
unenforceable for any reason, it shall be adjusted, if possible, rather than
voided in order to achieve the intent of the parties to the extent possible. In
any event, all other provisions of this Pledge Agreement shall be deemed valid
and enforceable to the full extent possible.

        14. This Pledge Agreement shall be governed by, and construed in
accordance with, the laws of the State of California as applied to contracts
made and performed entirely within the State of California by residents of such
State.

        Dated: March 23, 2000

                                     PLEDGOR
                                     JOHN HENTRICH

                                      /s/ JOHN HENTRICH
                                     -------------------------------------------

                                     Printed Name: J. Hentrich
                                                  ------------------------------

                                     PLEDGEE
                                     WebSideStory, Inc.

                                     By:   /s/ MICHAEL CHRISTIAN
                                        ----------------------------------------
                                     Name: Michael Christian
                                          --------------------------------------
                                     Title: Senior Vice President
                                           -------------------------------------

                                       4.

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