With the heat coming in you're probably hitting the hardest part of the growing season. Pollen doesn't flow properly in hot weather, causing the plants not to set fruit. South of you they don't even try; they split the season around the summer. Definitely seek out heat tolerant varieties. Your extension office could probably give you a list of what does well in your area, and tips on growing tomatoes in central Florida. You need to worry about diseases and soil conditions that we don't have here, so I hesitate to give specific recommendations.
Shipping would cost more than the tomato plants, I imagine. Starting from seed isn't too hard, but I'll bet there's local nurseries (not big department stores) which carry specialty and better adapted varieties, too. I'm sure we can help you locate local sources and/or send you seeds if you need help.
Tomato plants take 6-8 weeks from seed sowing to planting out, if temperatures and light are favorable.
