There are schools that provide light training and others that provide certification. Some pay you as you learn. You can be a handyman doing light jobs (read occupational code) until you get your certification, if you choose to become certified. Get started. Consult the following:
http://www.detroittraining.com/workshops
http://www.bricklayers.org (12-week program [free training], drug test, character references)
Raoul, (313) 587-4913, (bricklaying plus information about other trades)
Melody, (313) 779-1666, information to become a plumber
(313) 719-9921 (information about learning trades)
Consult the Michigan Occupational Code (excerpt on separate page): Act 299 of 1980
http://www.legislature.mi.gov/documents/mcl/pdf/mcl-act-299-of-1980.pdf
Website you might find useful: http://www.handymanstartup.com