1st place I would start would be to run iwconfig.
you should get something like..
ath0 IEEE 802.11b ESSID:""
Mode:Managed Channel:0 Access Point: 00:00:00:00:00:00
Bit Rate:0 kb/s Tx-Power:50 dBm Sensitivity=0/3
Retry:off RTS thr:off Fragment thr:off
Link Quality=0/94 Signal level=-95 dBm Noise level=-95 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
My card isn't configured but the above shows it is at least acknowledged by the kernel,and the cards associated drivers.
if it just says no wireless extesions detected or something along those lines;then you need to install the correct drivers for your wirless card on your system.