You obviously know to get bigger containers. Nothing smaller than the half-barrels. That's about a 30-gal. container, though. I personally recommend finding yourself a little patch of ground.
Since the soil is so sandy there, let me give you my recipe for a built-up bed. (I got this from a client of mine, who got it from a friend who had rooftop gardens in New York City. We built his beds a few years back, and he has had wonderful vegetable gardens ever since.)
For the walls of the bed, I use synthetic railroad ties, which are about 6"x6". I don't use real ones for two reasons: They rot and they contain creosote. Lowe's used to carry Everlast timbers, which are compressed plastic and asphalt. Loved them, but they were terribly heavy and don't seem to exist anymore. Now they have another type that are hollow, heavy plastic (like the Rubbermaid mailboxes, plastic kid toys, etc.) You cut them with a circular saw. Whatever you get, get 3 8-foot sections and cut one in half to form an 8' x 4' rectangle.
Fill with about 20 40-lb. bags of topsoil (I use the cheapest kind,) about 2 cu. ft. of peat moss, a couple of bags of Black Hen chicken manure (cow manure will work in a pinch, but either way don't use FRESH manure--see pee-pee post above!) a sprinkling of green sand and a sprinkling of bone meal (available at feed stores and the like.) Mix it up. Plant.
As for your bug problem, I googled organic insecticide tomatoes (no quotes) and got a gazillion results. I'm all about Sevin, myself...oh, well.
Good luck!