There's a tent made in Australia called the Oz Tent that looks like it was made for teardroppers:
http://www.oztent.com/
A Land Rover dealer in Atlanta sells them. Couldn't find any others. The Oz tent has an internal frame that allows you to set up in 30 seconds. Top quality, looks like a wall tent. Be sure to check out their accessories. And they aren't cheap, but in U.S. dollars knock off about 30% or so of the Australian Dollar price.
Wade