The most recent couple of versions of Windows Media Player slow down without pitch change too. View, Enhancements, Play speed settings.
Free download "Audacity" also does it AFAIK.
Tom
Close to my solution, I ripped them to mp3 with Nero, now play them back 1/2 speed with MP. Like night and day, they were recorded at speed, way too fast for instruction. At 1/2 it is managable to learn from.
Amazing slow downer os awesome, but a $50 investment for the full and more useful version.