Good luck! I dont know if it is my area or what, but I cant seem to find any good iron locally. I have bought most of mine from people on cast iron auction groups on facebook. If you are on there, it is a good place to browse. Only downside is shipping... Its all done via paypal, so if someone tried to scam you, you would get a refund. (Ive never had a bad experience though.)
Iron Man Cast Iron Auctions and Black Iron Cast Iron Sales are two good groups.