First, check with your local government to see what the licensing requirements are. You will need a DBA (doing business as) certificate. Buy books on locksmithing (inexpensive way to learn):
http://www.amazon.com/gp/product/0071448292/104-0070440-4230360?v=glance&n=283155

or enroll in a correspondence course (expensive way to learn, but has its benefits). Join an association like The National Locksmith. You will get a monthly magazine and an optional $15,000 bond with an ID card. Check eBay (search 'locksmithing') for supplies and educational material.

Hope this helps.

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