I had a wired network for years, no problems, I have a new wirless laptop and switched my router to a linksys wrt54g V8 my Lan works fine both computers network as always, I am encrypted and secure on wirless and have internet access, however everything I have tried to get my LAN networked computers and my wireless laptop to network has failed, please somebody help me!

you must be a little more specific,

Test A:
Separate computers can ping router

Test B:
separate computers computers can ping google?

Test C:
computers can ping each other

Test D:
filesharing is enabled and firewall is not blocking it

test F: files can be downloaded from one computer to another via the smb protocol.