Editing Audio with Audacity
Audacity is free, open source software for recording and editing sounds. It is available for Mac OS X, Microsoft Windows, GNU/Linux, and other operating systems. With Audacity, you can record live audio; convert tapes and records into digital recordings or CDs; edit Ogg Vorbis, MP3, WAV or AIFF sound files, and even cut, copy, splice or mix sounds together.
Exporting Audacity Projects as MP3s
Because of software patents, Audacity cannot distribute MP3 encoding software. To be able to export Audacity projects as MP3s, follow these simple instructions to use the free LAME encoder (works like a charm!). You'll have to do this only one time.