Audio Top-Level Contents
MPEG Compression
The CD includes a number of programs that will perform various levels of MPEG compression, including the well-known level 3 (MP3) at a wide range of bitrates. Read the individual descriptions, and try the one(s) that match your needs best. I have not included audio content (except for the .wav files in the Dolby demonstration) because several of these programs offer the ability to extract a file from an audio CD -- so you can create your own test material!
Dolby Demonstration
A great help to understanding how audio compression works.