No, I haven't read any of her books, but I am somewhat familiar with her most well-known book
Captains and the Kings. It was made into a TV mini-series in 1976. I remember following that and enjoying it very much. It's an account of a very wealthy man who manipulates the political system. There are strong parallels to the Kennedy family. Caldwell was a "secret money cabal ruling the world" conspiracy theorist and as I recall there were some things implied in the series that can't be stated in non-fiction. I'd like to watch it again if it weren't $90. (Reminds me of a friend I watched it with, a WWII vet who was POW in Germany, but no longer with us.)
http://www.amazon.com/Captains-Kings-Ri ... +the+kings
Caldwell was quite the psychic, but I don't know how much of that showed up in her books.
http://www.amazon.com/The-Search-Soul-C ... 0385025637
http://www.amazon.com/In-Search-of-Tayl ... XBBZ6J92NC