Aaron,
Start by ALWAYS opening Device Manager and removing the device before shutting the PC down to remove the hardware.
Next, check Add/Remove Programs, and remove any software installed for the device.
Next, Registry cleaners such as Norton Win Doctor and V-Com Fix-It do a fairly decent job of cleaning up the registry.
V-Com System Suite also has a registry compaction / defragment tool that can be useful.
Still, I have found neither tool to be the answer to clearing all traces of removed hardware.
It's time to learn to use regedit.
CAUTION: Improper use of regedit can disable your PC.
It is "best" practice to make a backup copy of the registry files before editing the registry.
A good guide to the registry is posted at www.winguides.com
Start at HKEY_LOCAL_MACHINE
Expand the branch and locate the ENUM key.
(I'm on a W98 box right now, and I know that the ENUM key is at least 2 levels below on a W2K system.)
Expand the branches and look for any hardware that is no longer part of the system. (and that you plan to leave out)
Note the labels of the keys and data for the device.
Delete the key(s).
Now search for other occurrences of the device name and terms. (Edit, Find)
Delete keys as appropriate.
Search for any new terms that you find for the device. (I've done as many as 5 levels of searches.)
After you exit regedit, it may be worth it to run a registry cleaner again.
Then, search the hard drive for driver file remnants.
For sound cards in particular, don't forget to search through the 'legacy' system files.
Autoexec.bat
Config.sys
Sys.ini
Win.ini
You can do this by running sysedit.
Chas