I did it once on a work computer. You should probably know a little about mac/unix to do it. if not at least some linux. The hardest part is finding drivers for your equipment. all of them have to be written by the open source community if they do not match what apple puts in their comps.
start by finding a torrent of Jas/iDeneb OS 10.5.5 and go from there.
the best site to find info is
http://www.insanelymac.com. Go to their OSx86 wiki and find a guide.
Good luck