When will my tomato plant produce fruit?

I bought tomato plants at wal-mart. Idk what kind of tomato, the tag doesn't say. I live in south texas. I planted about a month ago. It gets full sun pretty much all day. It has flowers, but the flowers die off and I see nothing coming in after it. I water daily. I have not used any sort of fertilizer. My bell peppers and yellow squash are coming in nicely, which are in the same bed.