I'm having trouble finding information on whether or not there exist any USB 802.11b or 802.11g wifi adapters that are compatible with Slackeware Linux. Does anyone know? I recently purchased an ultra small system, but it has no wifi card, and no room for expansion. So, my only option to get this on my wireless network is via a usb adapter. Please help!!!

Welcome to LQ.

You can check the Hardware Compatiblity List (HCL) here.
There's also a whole forum devoted to wireless networking here (but, you already know about that one).
Finally, you click "Search" near the top again to look up anything in LQ. This is an example.

As far as a practical answer goes, I use an old usb Belkin F5D6050 (802.11b) wireless card on Slackware, but you can probably find better ones now. I also don't think the particular distro you use is a factor.

Berhanie - thank you so much for responding to my post!

I actually took a look at the hcl before posting. I found the wireless networking section difficult to use, because it did not list the adapter type - only model numbers are listed. There is no way to tell looking at the list if an adapter is a usb adapter or not (unless the letters USB happen to appear in the model number). Is there a way to request this enhancement to the hcl? It would also be nice to see the protocol (802.11a/b/g) for the adapter.

The 2 specific model numbers that I did have, I did not find on there. It looks like I will need to look up all of the vendors sites first, find usb adapter model numbers, then come back to the hcl to see if they are listed as compatible. A bit cumbersome, but doable.

Thanks for your specific suggestion! I will see if I can find one of these older Belkin adapters online. I would prefer to buy something newer, though, if possible. Ideally 802.11g would be better too.

Does anyone else have any other suggestions for Linux-compatible usb wireless adapters?

You can request it. I don't think it's there now. But you can go to HCL and then do a search. This is what I found under "usb" when I selected all the "Network Cards" categories.

Yes.

Also, for the card I mentioned, I had to compile the driver (the HCL entry tells where to get the source code), which is something you may not want to do.