Audacity – Free Easy-to-Use Audio Editor and Recorder
http://audacity.sourceforge.net/

Audacity is a free, easy-to-use audio editor and recorder for Windows, Mac OS X, GNU/Linux and other operating systems. You can use Audacity to: a) Record live audio, b) Convert tapes and records into digital recordings or CDs, c) Edit Ogg Vorbis, MP3, WAV or AIFF sound files, d) Cut, copy, splice or mix sounds together, e) Change the speed or pitch of a recording, and f) And more! This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.