I sometimes use a program for Mac called Amazing Slow Downer (http://www.ronimusic.com/
) which allows you to slow down music without changing pitch, loop and a bunch more. It's relatively cheap and works great. There's also a windows version. Here's their description of what it does:
"Change the speed of the music - from 20% (one fifth speed) to 200% (double speed) without changing the pitch.
Wrong key? Change the pitch in semi-tones - at full or changed speed.
Out of tune? Adjust the pitch in cents (100ths of a semi-tone) to suit your instrument.
Real-time processing - all described above is done in real-time - just insert the CD and press the play button!
Also slows down MP3, Wave, Windows Media Audio, Ogg, FLAC and AAC/M4A files on your computer in real-time.
Note: M4P files from the iTunes store is now supported.
Great stereo sound quality!"