At the cost of being unpopular, guys, the editors and a few others contributed nicely to this thread. How come it has degenerated into self-advertisement? Stick to the topic and over time you'll probably find more people willing to play with you!
Personally I love the exhibitionism I read in erotic stories, but those are largely fantasies. In real life, at least in the western world, it's far more problematic. Even nudist beaches often aren't really for exhibitionism, only to enjoy the freedom of wearing no clothes, but not really for anything sexual.
I guess sex clubs are really the only way to go. We just need more of them in front of a beach. Are there any?