Hi Allan
Carefull with the cheap DVD players, I bought one and found it didnt have video in (despite an add that said it did), and had to take it back. Most are players only.
I ended up getting a mini LCD TV from JB on sale for about $320, I dont remember exactly, it was 2-3 yrs ago, they are probably cheaper now), to my suprise it had an external power supply which supplied 12v DC to the TV so I could use it in the field with a battery (it wasnt sold as a "portable" TV)!.
It also had an VGA PC connector and tuner . I used it with the video out of a EOS350D for focusing etc, worked very well, and the tuner was handy when I got bored
.
Cheers
Fred