Although I cannot help, I am having much the same sort of problem so will watch this thread with interest!
What is your setup?
I have Desktop running XP Pro and Laptop with XP Home. Had networked with cables and then installed the Buffalo 54g Wireless Router and cardbus. Now, cannot find networks at all. Have turned off all Virus/Firewall apps when running network wizzard but to no avail.
Have not yet (cannot figure it) set WEP but rely on MAC address access only for the laptop to communicate with the router. (Router is hardwired to the PC as well, so it is only the laptop that is using wireless).
Dont mean to hijack your thread but if there is any similarity then perhaps it will assist us both?