Yes you can put a car up there, I've seen some very small cars (Smart cars) that are winched up onto the truck and one truck that had a full size Jeep CJ on the back lengthwise. The trailer hitch had to be put on a frame extension. That made for a very long combination and also meant he had to have long ramps to drive the Jeep up on the truck.
We have a Jeep that we tow behind the trailer and that is legal in most states. If you are single that wouldn't be an option as there would be no one to drive the toad if you got to a state that it wasn't legal.
Go visit the escapees web site and ask there. There is a TON of info and options with the folks that post on that site. We all like helping newbies get started.