They are called "Rear end truck tents" (for SUV's), both Sheba and I had to buy ours from the USA. Should be some pic's on show us your rig, but here are a couple again. Mine is on a Mitsubishi Outlander, please note that for these particular ones you need either a smooth back or tailgate (ie; no fixed raised edge on the back of your SUV).
This was the one I had, advantages of it was you were off the ground and could move the vehicle if you had too without taking it down, just lift to bottom and tuck it in to clear the exhaust pipe. Also no pegs or poles to worry about. Where my rear seats folded forward, I need to pack the floor with some foam to bring the floor level up in the seat wells, but I left it like that all the time. I don't know why they don't sell something like this in Oz, they are so convenient and take about 5 easy minutes to erect. Hope this helps. Weevil aka Duh, aka Vic (past avatar handles with Cindy's approval). PS: Make sure you buy the right size for you vehicle which needs a flat rear floor at the rear. What type of vehicle do you have ?