Audacity Tutorials

* http://audacity.sourceforge.net/help/tutorials
* http://audacity.sourceforge.net/help/documentation
* http://www.transom.org/tools/editing_mixing/200404.audacity.html
* http://audacityteam.org/wiki/

Also of interest:

* http://mwgblog.com/archives/2004/12/27/podcast-about-the-podcast/