You have the Audacity

Audacity is free, software for recording and editing audio.
It is cross platform. Windows, Mac, Linux
http://audacity.sourceforge.net/

Record live audio.

Convert tapes and records into digital recordings or CDs.

Edit Ogg Vorbis, MP3, and WAV sound files.

Cut, copy, splice, and mix sounds together.

Change the speed or pitch of a recording. - this can help in learning or you can get through content faster. This can also helps a bit for you men out there who have difficulty hearing high pitched sounds. I think we developed this over thousands of years of evolution as a psychological defense mechanism.

Learn more about Audacity...

Wiki

Forum for more information.