I believe my wireless card is an atheros one, but it worked from a fresh install of 9.04. A few weeks ago I was having trouble connecting (turned out to be the router) but at the time I went System->Administration->Hardware Drivers, and there was one there which was labelled as some kind of wireless driver, and was disabled. I enabled it. Since then it has disappeared from the Hardware Drivers box (which now shows nothing) and my wireless has stopped working completely.
Clearly there was some kind of problem or incompatibility with the thing I enabled, but I don't know where to start to get back to the original setup. Reinstalling Ubuntu wouldn't be a complete disaster, but obviously I'd prefer not to have to resort to that.
If I do ifconfig I only get eth0 and lo (and pan0 if I do ifconfig -a). If I do lspci the only networky thing apparent to me is Ethernet controller: Realtek Semiconductor Co. etc, which I presume is for wired connections.
So any suggestions? Have I stopped it recognising the wireless card altogether, or is it just not loading the right driver? And of course, in these cases, what should I do?