Music editing program?

what program can i download for FREE that lets me edit music files and also lets me put them back in CD's?? right now im using Audacity 1.3, i can do all the things i want to do....but it turns the music files into some other type of file that most other players can play.... is there a program that lets me edit music and leave the music files in a format like mp3, wma or something like that??? thnx