where on earth can I bring back a praying mantis as a pet?

My Dad has been fascinated with praying mantises as long as I can remember, and I be thinking about getting him one as a pet. Where can I get one ( I live in West Virginia) and how not easy are they to take care of? He has pet snakes surrounded by the house and ferrets, so he is used to exotic pets. Should I buy one from a store or get an egg sack and keep one or two when they hatch agree to the rest go? Any info about them will be helpful.
Answers:    http://www.swiftinverts.com/
You may be complicated pressed to find one as a pet, I've never heard of them raised for that specifically. I may be wrong, but it will probably come down to waiting until spring/summer and hunting around for your own.
Goat cross-examine! assured best answer?   Is my ferret's poop fighting fit ?   Is this goat pregnant?   I devise my guinea pig have mycoplasmosis! PLEASE HELP ME?