I just came back from my Miami FL business trip. Thanks to all who posted on hobby stores in the vicinity when I inquired on this forum a few weeks ago!
Due to the immensely busy schedule, I didn't get to visit any of the recommended shops. On the other hand, I did manage to sneak out during lunch time to a shop I discovered relatively close to downtown Miami. This store wasn't mentioned in the previous postings, leading me to think it is relatively new.
Micro Macro Mundo is likely the second biggest Tamiya distributor I have seen (the first being Stargek in Singapore.)
This store carries nearly all the armor kits seen in the Tamiya catalog in multitudes. They also have a very complete selection of Revell airplane kits. I think I also remember seeing a good selection of Trumpeter ships.
They also have a good selection of Tamiya Acrylics since the recent Japan earthquake/tsunami disaster.
On the other hand, they are primarily a Tamiya supplier so if you are looking for DML or other brands, you are outta luck. Still it is worth a visit if you are in the area. It is a 15 to 20 minute drive down south from downtown Miami.