Where do you find DC electric motors?

Lots of things - your car has a engine that is used as a generator (your alternator). Cell phones that vibrate have a small electric motor with an uneven weight on the rotor which causes vibration as it spins. Fans (heater, attic, computer, etc.), many different toys - remote control cars, some airplanes, etc. Electric Golf carts and cars. The list goes on and on.