Audacity is a free multi-track audio editor and recording tool that has a ton of features. If you are looking to record audio, I highly suggest contacting a local music store to see if they rend high end recording devices. You can download Audacity here.
Fruity Loop Studio
Learn the secrets of the pros on how to make beats in Fruity Loop Studio.
If you are interested in creating your own music for your game, check out MuseScore. It will allow you to compose music with some basic understanding of music theory. You can download it here.