linux wireless - again...

[dcw@pr]

i'm venturing into linux for the first time, using ubuntu. I've got a wireless card, and it seems that the drivers are all installed OK. When i do the iwconfig command, it comes up with all the right information. But I cannot find any networks to join, when I try to scan it comes back wih " No Scan Results". I'm not convinced the card is working properly - there are no flashing lights on the back. any ideas?