I just set up a wireless connection at home. I bought a d-link 54mb/s router (DI 624 I think). I have a G4 laptop, which has an airport card (only 11mb/s) and connection to the internet was a breeze.
I haven't yet set up a network, but if you use XP and OSX then they both communicate using the same protocol, so its meant to be easy.
You can also buy programs like "Dave" to help out with pc/mac networking, but they aren't required these days.
in summary, both can operate on the 802.11a, b or g so there isn't any real problems.