hey yeah that's what ive been doing. It's got an inbuilt speaker in the monitor but u can connect it to normal car stereo if you want.
The unit in the second pic is wat runs to the screen.. so you can run a gps system, dvd player, playstation/xbox, (ipod video.. if you can get a connection to rca's im not sure).
Any other questions feel free to ask:)
You can always just buy a slimline dvd player or something for 50bucks and buy an inverter from dicksmiths and connect it up to the monitor and it will play fine. Just needs a source to get the video from.