Im needing some help setting up a home network,primary computer has vista home preminum,second computer has XP home edition Third computer has XP Home and is a lap top that I want to be able to use in other rooms in the house.I have cable DSL modem with a Linksys Router(WRT54G).Using Netmagic notable to get things set up right between three computers.Need someone to walk me through setup process.Thanks.James.

Here's a decent article that walks you through each step.
Setting Up Wireless Access Pointsummies

The one issue may have is if you want to share files or forders from the Vista machine. It handles sharing differently. Vista help (F1 from the desktop) has some decent information.