When I was using a PC, I would always use Audiogalaxy Satellite to get MP3s. If you don't know, it's a combination of a client program and a website database. You search for songs on a website and select songs to download. Then you run the client program and it downloads the songs. You can select songs anywhere that has web access. The client finds the person closest to you with the best ping and downloads from him. It supports resumable downloads from multiple people and will wait for the person who has a rare song to log on. Anyway, I just found out there is a client now for Mac and Mac OSX. Go to versiontracker.com to get it. Be sure to set a download folder or it will crash.