I was having problems with lock id, bought this new book from safeventures when buying some picks, and now i have no problems, loads of info and instruction on identification , fitting and non destructively opening each lock, helped me big time.
http://www.theinstituteofcertifiedlocks ... manual.htm
There are lots of id cd about but i bought this as its written by 4 working locksmiths and fully supported and endorsed by safeventures, sks and the ICL,