Slashdot once again does our homework for us. http://linux.slashdot.org/linux/07/05/07/159250.shtml
Basically the Keyboard Magazine website, http://www.keyboardmag.com, has broken down audio production on Linux into a quick and concise beginners guide to getting started. Lots of links to distros and OSS relating to audio production, including the Linux analog to Pro-Tools, Ardour.
Peep it, yo!