So after doing more research, it turns out that Southern leopard frogs (which are what is commonly sold) probably wouldn't survive here. On the other hand, Northern leopard frogs are native to my area, however there is a possibility they may go on the endangered species list. The common theory is that they are dying off due to increased use of pesticides. I'd really love to provide a protected habitat for these guys, but of course my pond isn't big enough to support very many. However I've been trying to find people I can contact to see if there are any programs for such a thing, so maybe someone will be able to hook me up with some eggs or tadpoles.
In the meantime, I've also run across a "plains" leopard frog, which is more of a brownish color - also native to my area, but also nowhere to been seen, nor can I find a source for them. Of course plenty of pet stores have bullfrog tadpoles, which I have no interest in. *sigh* It sure is hard to find suitable inhabitants for my garden!