Yeah, sadly, Huntsville doesn't have the greatest selection to choose from. I've also found Windmill to be pricey.
But if price is not a problem, check out Great Spirits next time you're in town. They have some hard to find items from time to time but will make you pay dearly for them. (I paid $75 dollars for my first bottle of Bookers only because, at the time, I thought that was the only place it could be found. Man was I wrong, but the damage was already done. Even a fine bourbon like Booker's couldn't take the edge off that gouging!)
I haven't been able to locate Old Fitz 100 anywhere in North Alabama. Old Forester 100 is not easily found and is badly outnumbered by the 86 version....but it's around.