Congrats on actually finding something in a Fort Myers thrift store. I've stuck with Play N Trade for my NES purchases. The store in the Cape is awesome as hell. The majority of my collection (Been collecting seriously for about a year...) is stuff I've bought from the Cape PnT.

I've had luck with the Capital Pawn in Naples before, but most of their games are fairly new, and the prices were kind of expensive. The one in Bonita used to be a damn oasis of games, but I haven't gotten anything worthwhile from them in years. The Bonita location actually moved a few months ago, so maybe they've got some different stock...