im using frostwire right now and its fast for the most part but i can never find anything that im looking for unless its a really well known song. i suppose that has more to do with the clientel than the prog though?
Try torrents.
I’ve been using eMule. I’ve used a little bit of everything in the past, but this is the quickest and I usually find everything I need.
I don’t know where I found it, but peer guardian is a good thing to have too.