First of all, what kind of camper? Trailer, 5th wheel, motorhome? Something that goes in a pickup bed?
A month ago, I replaced the old tube-type analog TV (broken) in the motorhome with a little (22") HD set that I found on-the-cheap ($175) at Best Buy. I thought about how I could properly mount it for weeks. I finally decided on a fold-away "under-the-cabinet" mount that I got for about $60 off the Net. I'll take some pics and post them to this thread in a bit. (The RV dealership where I've been getting a lot of the work done on my RV was so impressed with the mount that they're going to buy them as a standard stock item for their facility.)
The problem is that the walls of a camper are generally not thick or strong enough to hold a flatscreen mount. Particularly if your set is plasma, or over about 24" in size. That's why you basically never see a mount attached to an outside wall of a camper. You probably won't be able to do what you want.
The first pic is the space the original tube TV came out of. It was so broken that when I pulled on it, the front plastic around the tube broke into pieces. The next pics show the mount and the replacement TV. I had to pull the "false floor" out of the cabinet and glue reinforcement blocks to the frame inside, because the cabinets (as you no doubt know already) are just thin paneling. I also had the RV dealer wire up a 110v outlet inside the cabinet, pulling from the already existing outlet on the underside of that cabinet. The mount is plainly visible, and I installed it in under 45 minutes from drill to done.