Josh said:Um, what are we talking about here, dialup, cable, or DSL?
The model you listed is an ADSL modem, in which case, if you're living in the same house, you get a router, and you share the connection. Another modem would be the same as adding another DSL account, and will cost you a lot of extra money a month.
Josh said:Best router in my opinion is the Linksys WRV54G. Buy it at best buy, get yourself a wireless network adapter for your computer, and follow the setup instructions that come with the router itself.