Freditor reports that the Jan-Mar 2007 issue of Filmfax
Magazine contains an interview with David Ossman (and
quotes from Proctor & Bergman) that was conducted a few
years ago.  This issue may still be on newsstands, or
do what Fred did and buy a copy on ebay.

A power so great, it can only be used for good or evil.
  -- Firesign Theatre