Music optimization/loading

My latest game is about 90% done. A number of people have commented on the lack of music. I've found an artist who was gracious enough to allow me to use some of his tracks in the game. Right now I have two tracks totaling about 4 minutes of music, which takes the game size from 2.7MB to 6.6MB.

1.) What's the best tool/method for compressing mp3s while keeping decent quality?

2.) How do other games deal with the size of music? One potential solution is to load them into the game after the fact, although this has the downside of making game distribution problematic unless I'm willing to eat the bandwidth cost of hosting the music on my server.