Sata is the way to go. I wrote two article on sata cards on this site, check em out. They run much faster than your standard ata-66 hd bus. As for sound cards, the only mac versions I know of are M-audio which are great and start around a hundred bucks. You could get a usb audio in/out. There are a few for macs that will give you mini phono preamp in/out. That would be a cheaper route.
-maestro