Don,

If you're USB adapter is supported in linux, it should "just work."
You should be able to check the output of dmesg to see if the hotplug
system found your USB network adapter and the driver for it. A quick
google search should tell you if your USB network adapter works in
Linux.

In general, Linux doesn't view a wireless network adapter any
differently than a normal network adapter. Just need to add SSID and
your WPA info and you're off and running.

Before purchasing hardware, start by searching. http://www.google.com/linux
Keep in mind you'll usually pay a little more for hardware that works
in Linux. Before you gawk at the price tags, keep in mind you usually
get better quality hardware. :)

I recently purchased two PC Cads from CDW. Cisco Aironet 802.11a/b/g
Wireless CardBus Adapter (CDW part #578730)
Proxim ORiNOCO 11b/g PC Card Gold (CDW part #634350)

Both work like a champ in Linux. Proxim has a PCI card that should work as well.

When shopping and checking compatiblity, avoid cards that use
ndiswrapper if you can, as these cards don't have real Linux drivers.
ndiswrapper lets you use the ndis drivers in Linux. ndis drivers are
usually used for performing network operating system installations.
Many people have had success with ndiswrapper, but I perfer to support
hardware vendors that are Linux friendly. :)

Another option I've used in the past is to get a Wireless Ethernet
Bridge. These devices are commonly sold to XBox, TiVo, PlayStation2,
and others who have a device with an ethernet card but no wireless
support. I think they are great solutions for a Linux desktop.

I reccomend the Moterola Wireless Ethernet Bridge WE800G or SMC EZ
Connect g SMCWEBT-G. These are the only devices I've found that
support WPA encryption. Setting up these bridges is easy. You set your
ethernet card to a static IP, pull up the devices web config, enter
the info for your wireless network, save. Then configure your ethernet
card for DHCP again and you're off and running on your wireless
network.

I use these at work because we have technology impared customers who
have laptops but not wireless cards. Instead of loaning them a
wireless card which they may not be able to install drivers for, we
give them the bridge device and they are off and running on our guest
wireless network. Slick! You can also connect the bridge to a swich
and connect mutiple clients to the swich and you'll be off and
running.

-- 
Andrew S. Zbikowski | http://andy.zibnet.us
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