I am not aware of any books that address this specific topic.
Articles have appeared occasionally in magazines about mounting
cabochons in leather. Try back issues of Leather Crafters and
Saddlers Journal:, Leather Crafters &... E-mail Address(es):
For hole punches try Leather Factory locally. Ask for their business
price list if you have a resale license. For mail order try Weaver
Osborne is a good brand of tool for
professional use. I would avoid the hobby craft level of tools if you
plan to do any quantity of leather work.