The most recent issue of ReNew (the ATA's magazine) has a pretty comprehensive review of solar power - panels, contractors, issues, processes, rebates. It's a good read/resource if you're thinking of going that way.

Hot and humid is an awkward combination to get good cooling. I've started looking into solar thermal, which works well in hot+humid conditions, but such systems don't seem to be currently available at the residential end of things. (The idea of solar thermal is that you're using the sun's heat - not light - and it usually works by driving a desiccant cycle that can pull the water out of the air, reducing the uncomfortable humidity so that less actual cooling is needed.)