help with wireless airport

I need a little help setting up my airport extreme card. I'm new to a mac computer and don't really know a whole lot. I have my interent working on my PC with my router connected, but I can't seem to figure out how to get my airport extreme to detect it. Can anyone help me with this? any response is greatly appreciated

Thanks
Jason

well I got it connected sorta. The internet is working but I dont think i'm connected to my wireless. It says i'm connected to belken54g but I have a linksys router and there is a password on my which it never asked for. How do I get it to detect my router