bruce said:
Linksys WAG354G 4-Port Wireless-G Broadband Router (NW-044-LS)
- ADSL2+ Modem, Internet-sharing Router, 4-Port Switch and Wireless-G Access Point in one box
- High-speed ADSL2+ Modem gives you a fast, "Always On" connection to the Internet
-Connect your home PCs using the built-in Wireless-G Access Point or to the 4-port Ethernet Switch
- Advanced Firewall, Content Filtering and Security features protect your PCs, your data, and your family
http://www.overclockers.co.uk/acatalog/Wireless_Routers.html
That should do what you want to do. You'll also need to connect your 360 to the network either with a long cat5 cable or with the MS wireless adapter.
I personally really like linksys stuf but there are cheaper options that'll do the same thing.