If you're looking for ways to improve your basic stalking skills for pursuing prey animals while hunting, paintballing won't help much. It is a lot of fun though. Basically, humans are easy to stalk up on. When compared to the average deer, a human is deaf, blind and has no sense of smell. We are also clumbsy and noisy, even when compared to an animal as large as a Bear or Elk.
As a youngster, my first experience with learning to stalk was to watch cats pursue their prey. Ever notice how easily they could hide behind a blade of grass? Or seem to anyway. Or when they knew their prey could see them, they froze and didn't move a muscle. How smoothly they move, how low they get to the ground and how gingerly they took each step as they approached their intended target and how quickly they struck when they were within range. They always approach from downwind and take advantage of other noises before they move and never look their prey in the eye. Even though we aren't cats, we can utilize, if not perfect their methods of hunting and the more you use them, the better you will become at them.
One book that I'd recommend on stalking and still hunting was written by a traditional bowhunter named G. Fred Asbel. The name of the book is "Stalking and Still hunting-The Ground Hunters Bible".