I'm not sure whether or not you've used Windows before but after installing the drivers I simply configured the Airport wireless device like any other wireless device. Let's say you're base station's running DHCP. Just go to Control Panel -> Network Connections and right click the airport device. I don't remember whatever the name was right now but you should be able to figure it out. Most likely there's only one wireless device, if not the bluetooth device shows up as well. Anyhow, choose preferences for the connection and that should bring up a new window.
Here you can change settings for IP and choose from available network (second tab). Most networks shows up automatically but you can add networks manually as well. IIRC you should be able to pull up a list of all the available networks from the second tab.