Hello, black1...
You might try looking up Rob Neto...he goes by the user name dive-aholic on Scubaboard. He has a mentorship class in how to use doubles. He works out of the Panhandle, though, but I'm sure you could talk to him about the possibility of maybe scheduling the class a lil' closer to your house (I have no idea if he's willing to do that, but it's worth a shot).
Barring that, you might try to find an instructor who teaches TDI's "Intro to Tech". This is usually a two day class, and is designed to introduce the recreational diver to technical diving gear and procedures, such as air sharing, valve drills, and so forth.
Now for the big question: Why do you want to learn to dive doubles? If your Scubaboard profile is correct, you've got under 25 dive's worth of experience. I don't know about you personally, but at 25 dives, I was still trying to get the hang of the basics, such as holding a horizontal safety stop, finning without kicking up the silt, and keeping track of my buddy. I couldn't imagine adding on doubles at that point. It's not just the extra tanks, but other stuff you've got to consider, like making sure you have enough lift in your BC or wing to be able to float those tanks, having a redundant inflation in case of wing failure, such as a drysuit or a double-bladder, etc.
If your primary reason for wanting to learn doubles is that you're burning through air like it's going out of style, there are other ways to increase your dive time without resorting to doubles. A large single steel tank can give you as much air as a small set of doubles, without having to buy a larger wing, learn valve drills, etc.
Plus, as you increase your dive count, you'll discover that as you gain experience and relax a bit, your air consumption will decrease quite a bit.
Anyways, I'm done pontificating for the night