Are the blooms falling off if they are you have bloom rot there is a spray I think.Try growing your on plants from seed less chance of diseased plants.good luck Jim

I tried for four years in the ground and got a few tomatoes in May and then when the rain came around in June, I stopped getting any and my plants drowned. This year I planted three plants (Early Girl, Better Boy and Creole) deep in huge pots (18 inches tall and 15 inches wide) in good potting mix very early in March and hauled them under the porch when it got chilly. Could you be having too much rain to polinate your tomatoes? I have at least 40 or 50 tomatoes right now from these three plants and would have had more but for the caterpillars. Maybe try planting early next year and try some early fruiting varieties (early girl) in raised pots.

Try shaking each plant to help in pollination. I was having same problem until I posted on Tomato Forum and this was advice given to me.
I am now eating tomatoes.