Your question isn't entirely clear - are you after an explanation of CAT 2 and 3 Ops, or how to do CAT 2 and 3 approaches on a 737?
I have found this pdf doc useful for explaining the way CAT 2 and 3 are set up:
http://www.wingfiles.com/
First section is headed APPROACH, fifth doc down is "Getting to Grips with Category II and III Operations". It is an generic Airbus document.
BE WARNED - it is 13 MB to dowmload.