jaydee2 0 Light Poster

Not sure where to post this, but here goes.
I have a PC running Win XL pro (sp3). It has a DSL service connected and running. I have a MAC I-Book G4 that has no internet service unless I use the internal modem and dial up.
I have used a router and networked the I-book, my desktop PC and another desktop PC (running Win2k sp3) on occasion, but I found it to be less than reliable (BellSouth is the ISP).
I would like to access the XLpro PC with the Ibook via a wireless setup.
What do I need? How do I go about it?
tks,
johnd