check your wireless chip. Atheros and ralink chips are well supported. check the following links: 1.linux driver http://linux-wless.passys.nl/query_hostif.php?hostif=Cardbus Atheros: http://madwifi.org/wiki/Compatibility 2.Card chipset http://users.linpro.no/janl/hardware/wifi.html
intel 3945 abg? try the following link: http://ipw3945.sourceforge.net/ (note: There is a link on the page which refer to intel made linux driver,You could use this one first). some discussion about 3945 on fc5: http://www.linuxquestions.org/questions/showthread.php?t=445715
broadcom? This company refused to give any information or sample to the Linux community because they believes Linux would change their software control and against the FCC rules. (well, Atheros gives a binary driver which keep both parts happy). But they had a stable Linux driver for themselves and gave it to linksys.
Now Linux has a broadcom driver from linksys because linksys using GPL license. This chip does have a origin linux driver which could not support all functions as windows does. So the ndiswrapper is the only choice. origin broadcom driver