Here is the information I used to study (and pass!) the CPCS exam.  

 

Joint Commission Standards - MS, and the appropriate areas of HR and LD

NCQA Standards

FSMB history, member boards and exam steps

Legal cases

Medical terminology

Study questions from previous versions of the test

The book "Verify and Comply"

 

If you're in California, ignore Title XXII and CCS rules.  Yes, that's hard to do, but this is a national test, not a state-specific test!

 

There are also various online study groups and forums on Yahoo and elsewhere.