An interview Phil Proctor did back in 1998 at Minicon, a
science fiction convention, is now up on the web.

You can get to it from Firezine's "Firesign on the web" page:
http://www.firezine.net/fstonweb.htm

Or go to it directly, here:
http://www.romm.org/audio

Phil and his wife, Melinda, and David Ossman all performed
as part of opening ceremonies; audio & pictures are here:
http://www.westley.org/pm.html