blackhawk

Newbie question about setting up a network.

I have a combined wireless adsl/router (netgear 834G) connected to a desktop PC via ethernet (router IP is 192.168.0.1, PC NIC is 192.168.0.2).
Wireless is turned on and I can connect a laptop (IP 192.168.0.3) wirelessly to the internet.
I also have an Asus w500g wireless router that I want to eventually connect to a Topfield PVR.
I cannot see the desktop from the laptop or vice-versa.
What am I doing wrong?
Do I need another NIC in the desktop connected into the router in order to be onto a network, or to run a hub from the router back to teh desktop?

Any help appreciated.
Thanks