Encoding/Conversion

MP3 Diags

Tired of having to go through your mp3 files and trying to figure out which one will work and which one won't? If you need help in sorting, fixing and changing information on your audio files, then you have a handy helper in MP3 Diags. MP3 Diags is a program that will help organize information in your audio library, scan and fix any corrupted files that might be stashed away somewhere and will even allow you to take a glimpse inside the body of an MP3 file. Essentially, the program is an efficient way of fixing your music files.
audacity

Audacity

Audacity is an user-friendly, free & open source audio editor. It is currently available for almost all operating systems, including Windows, Mac OS X, GNU/Linux and others. The software gets great reviews and ranks up there with some of the best in it's genre because of it's "clean interface, excellent features, and support for 32-bit floating-point audio" (and a great price - FREE! - if I may add). With Audacity, you can easily record/import audio, edit the files, add effects, and export to your desired file format.