One of the best rows I have ever seen on television happens just after the 26 minute point in this documentary:
It's worth viewing in its entirety if anyone has the time. The BBC reporter is, I think, the one who got into trouble in North Korea later in his career.
There's also an excellent biography of L. Ron Hubbard called Bare-Faced Messiah by Russell Miller.
Oddly, the rather wonderful counter-cultural novelist William Burroughs dabbled in Scientology for a while. There are a couple of books about that too.