I don't have any experience with ZMA, but bodybuilding websites and forums are packed with guys trying to increase their testosterone levels. Just google "bodybuilding," click on the first one, and head over to their forums. They can point you in the direction of the best testosterone enhancers, just browse the threads. Don't out yourself on the forums though, the majority of those muscle-heads are not LGBT-friendly! Alternately, PM me if you'd like and I can send you some links! 🙂