Audacity
Use – to edit sound files
Cost – Freeware
Description
A digital sound editor with drag and drop editing of .wav, .mp3 and ogg vorbis files.
Useful Downloads:
sourceforge
mp3 add-in (lame 3.96)
Portable Version:
http://portableapps.com/apps/music_video/audacity_portable
Tutorials
Online tutorials