About sources dealing with the Hollywood Anti-communist Era:
 
You probably know about this already:  a readable source aimed
at a general readership is Stefan Kanfer, _A Journal of the Plague
Years_, New York: Atheneum, 1973.  This includes a good discussion
of the "secular" anti-communist groups, as well as government
groups.
 
Hope this helps!
 
Matt McAllister, Virginia Tech.