To stimulate your own production you could take a look at bulbine natalensis, which will elevate your own natural production of testosterone. Bulbine natalensis is the active ingredients in one of AD's top products and if you'd like further information on it, feel free to ask.
The next thing I'd look at is Creatine, A simple monohydrate is good enough for some, but I happen to like MST Cre o2, a great product IMO.
But before all of the above, I'd have a look at one thing first, your DIET! As you don't mention it in your post, so I'm not sure if it's good or it could be improved.
If you need any more info, il be happy to help.