The card works. Windows is f#cked up. surprise surprise.

Open up Start -- Control Panels -- System

Go to the Device Manager or Hardware tab (been a long time since I've worked
with Win98).

Click the "+" next to Network Devices.

Your card may be there, it may not. It may be there with a yellow
exclamation mark on it meaning it's not working for some reason (we've ruled
out hardware problems). If it's there, highlight it, right-click it, and
choose "properties". Look through the various tabs for a check-box called
"disable in this hardware profile?" If it's checked, you've found your
problem. Uncheck it and reboot. Treat yourself to a warm flat Diet Fresca
for your prowess. If not, read on...

Highlight the card, and delete it. Yes, delete it. If any other network
cards are there (I assume you only have the one), delete them all.

Now, highlight "my computer", the top of the hardware tree, right-click and
choose "scan for hardware changes". This will force Windows to scan for
Plug 'n Play devices which are connected.

It will find the network card and re-install the driver. Win98 MAY be smart
enough to ask if you want to use the existing driver it's found in
C:\Windows. Ansswer "yes". You may need to reboot after installation. The
card CAN be activated without a reboot, but Windows is SO SO BAD
(particularly the non-protected OS versions like Win95/98/ME) at anything,
ANYTHING!, on the fly that it's probably worth it at this point to reboot.

Does it work? If yes, congratulate yourself with a trip to the drive-thru.
If no, download the proper card driver from the vendor. Open up the device
manager again, highlight your network card, right-click, and choose
"properties". Somewhere on one of the tabs (Driver tab, maybe?) there will
be an "update driver" radio button. Use it to point to the new driver.

Does it work now? If yes, go grab a cold beer and your ladyfriend and
reward yourself. If not, read on...

Open up Control Panels -- Networking. If you see TCP/IP listed, highlight
it and choose "remove" or "delete". yes, just do it. Now, whether you've
just deleted it or it was never there to begin with, choose "Install", one
of the buttons below the list of junk, or maybe beside it. Highlight
"Protocol" and click "Add". Find Microsoft TCP/IP, highlight it, and click
on "OK". You'll need your Win98 CD handy. It will re-install all (TCP/IP)
networking components. Reboot.

If this doesn't work, go on eBay and buy a similar machine for $20 or less.
Life is too short to go through this much trouble for an ancient machine
with a bug-prone OS.

OR, buy a book which will teach you the BASICS about computer networking...
TCP/IP and NetBIOS haven't changed in 15 years. You'll be more
well-informed, happier, and if you choose to get another machine,
transferring your old data will be a snap with your new skills and an
ethernet crossover cable.

Good luck.

Dave