Hi,
I have recently installed a Sonos system which fits in nicely with some of my existing hi-fi.
This links to my mini-mac and 500gb hard-drive with all my music on. Must say it is very impressive. Only have 2 zones at the moment (Lounge and Bathroom) but will expand into Bedroom and Kitchen/Dining room once house extension is complete (not started yet!) Works well on wired network (have 27 cat5e outlets in my house) but should also work wirelessly.
Definitely recommend.