How are you connected online?
If you have cable modem or dsl line, I would suggest a 4-5 port Cable/DSL modem with an integrated switch. This will connect to your ISP and appear to them to be one machine with a process called Network Address Translation (NAT). On the "inside" you can connect up to 253 machines by chaining together networking hubs or switches. If you only have 2 machines, you don't have to worry about it.
Wireless is great if you have a laptop and want to move around but be online. However, Wireless units are a little more expensive than wired and so are the NIC (Network Interface Cards).
Here is what I use to do what you're talking about
:
This can be found at:
http://www.linksys.com/Products/prod...id=23&prid=415
HTH!