I use something called a "dead sled" - basically a thick sheet of black plastic with tie down straps included. It also comes with a handy heavy-duty nylon strap. I slide the deer on the sled after it's dressed out and then drag it back to the truck. The sled doesn't do anything to make it lighter - I always swear I'll never do it again! The sled does help it slide across all the crud o the forest floor that snags and hangs you up while dragging the deer.
I've been thinking about buying one of these or packing in a tarp but it kinda sounds like a game cart would be the best way to go. In the past I have talked myself out of hunting certain spots because I knew that if I killed anything I never would be able to get it back to the truck by myself. I hunt public land so no ATV's or driving my truck to the deer.
