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.
Power Sound Editor
Power Sound Editor Free is a visual audio editing and recording software solution, which supports many advanced and powerful operations with audio data.
Mp3DirectCut
mp3DirectCut is a fast and extensive audio editor and recorder for compressed mp3. You can directly cut, copy, paste or change the volume with no need to decompress your files for audio editing.
Music Editor Free
Music Editor Free (MEF) is a multi-award winning music editor software tool. MEF helps you to record and edit music and sounds
Wavosaur
Wavosaur is a free sound editor, audio editor, wav editor software for editing, processing and recording sounds, wav and mp3 files