Wi-Fi

I own a new iPod touch 8 gb. But I do not a Wi Fi network in my home. I also own two PCs which are presently networked via a broad band cable connection. I was told I can invest i n a simple WiFi router with a short range of about 25 meters though walls so I can use all my WiFi devices. I also own an HP iPac so Wifi is very important for me.

Other than using suitable software to get a proxi address for the PCs and the router, I need to know what all pieces of hardware are required to set up my WiFi network.