Neem oil is a good insect repellent as is oil of lemon eucalyptus. As for the ants, try this: Grind up black pepper and crush it into powder. Spread it where they are seen, esp. on their trails in and out - bottom of doors, along windows, etc. Takes about a day or two, but the black ants will go away. Have faith. They track it around on their feet and they don't like it. Breaks their scent trail, I figure. Maybe cayenne would work too, but I haven't tried it - might be fun to try that on "red" ants sometime. Just powdered pepper - you don't need anything else. Clean it up in a week or two. They usually don't come back anytime soon.
Do you have any eucalyptus plants? Might be worth it to plant some. Here's another couple of links you may find interesting:
http://www.mosquito-zapper.com/Mosquito_power_trap.htm
http://memphis.bizjournals.com/memphis/stories/2006/05/15/focus2.html?jst=cn_cn_lk
As for it being hot and humid in Florida, I can sympathize. The last several summers here in Southern Ontario have been boiling hot, humid as hell and so full of smog that you can barely breathe. The pollution comes down from the nickel mines in Sudbury, across from Michigan and up from Texas and congregates over the Great Lakes. The pollution picks up on the water particals and dumps all kinds of crap over us. Last year I read that 9500 people here will die each year simply because of the "toxic soup" mix. This year so far has been the exception. It's been very rainy and cool this year.
Florida might not look so bad (except for the snakes) when you're faced with shit weather like this for 6 months out of the year:
