I did the NRI locksmithing course, then started a formal apprenticeship while working for my dad. Basically had 2 years and a bit of technical school and four years trade experience before I started my own business.
I would completely disagree with the above poster. Experience is indeed valuable, but its awful nice NOT learning by making making costly and often foolish mistakes on a job...especially on someone elses doors.
If you find your wanting to start into business before really learning the trade, make sure you surround yourself with a network of information (people, interweb, books, programs, etc.) that you can go to when having difficulties. Good training is just as valuable as experience, and makes your learning curve that much easier and fun.
