Central OK,
Google "dutch ovens" and you will find all kinds of websites and users who will preach the gospel of cast iron. OK and Texas seems to be a hotbed of such groups, as is Utah.
Intersting history behind cast iron, most notably for use on the Lewis and Clark expedition. Anyplace that was "settled" has a lot of the old time recipes and interest in cast iron cooking.
Me, I keep my eye open at yard and estate sales as many of the "kitchen cowboys" today seem to feel spending $800 on AllClad pots and pans is the only way to go. I have a couple $3.00 Dutch ovens and frying pans.
Full disclosure: I also have AllClads in my Kitchen, but a nice set of cast iron in my garage closet for camping, tailgating and sometime use on the outdoor grill. My Dutch Ovens sometimes get used inside.

Suggestion: Only buy American, Lodge prefered, as the asian cast iron is inferior in everyones opinion... older the better. Check out Ebay as well.
I would rather have an old one than a new one anyway.