Can I add wired network to wireless via USB Adapter

Belkin gear. I have a Access point in location A with main computer &
Internet connection etc.
Location B (50m away) Have another computer with a USB Network adapter which
works fine.
I have a laptop at location B & wondered if I could using wired cable etc.
connect to this computer & join the network.
I am guessing not as I imagine it should talk to the AP direct acting as the
router. Hopefully I'm wrong but would like some advise.

I have tried numerous PCMCIA wireless card and I can't get any to work prob.
with my 1996 notebook so looking at alternatives.

Thanks I/A
Greg