I find it a little worrying that someone would be about to start a CPL course without knowing how to do a mass+balance calculation. You should have done this for your PPL exams, your PPL skills test, and then again for your ATPL or CPL exams! The exact method is slightly different for every manufacturer and every type, and it's difficult to give examples without graphs (which I obviously can't do here). Go back over your ATPL notes, get hold of the POH for the aircraft you fly regularly, or have a chat with an instructor (PPL or CPL instructor should be able to help you).
For your skills test, the only weight and balance you will have to do is the weight and balance for your aircraft on the day. Ask your examiner his weight before the start of the test, know your weight, and know the weight of any flight cases or anything else you're taknig with you, then put all of these numbers, together with the runway length, pressure setting, temperature, etc, into the graphs or tables for the aircraft you'll be using for your test.
As for books - no, I don't know of any published reference material at all. It's for precisely that reason that I wrote my
CPL diary - have a read of that, I hope you find it useful.
Good luck!
FFF
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