The screen uses a standard RCA connector which is commonly used to component video.
As far as providing power the screen draws ~6W@12VDC. You will have to connect it to the ACC line in your car either directly or though the cigarette lighter. I dont know what kind of plug is on the screen so I cant be more specific than that.
However that being said if you have a double din area(not sure if the celcia has one) You can buy a lilliput/xenarc and put it flush mounted in that space - but you will most likely have to build a custom bezel if you do that. Personally this is what im doing.