Hi,
I grow various tomatoes in my greenhouse. In general, all tomatoes are perennials, although I have only ever grown indeterminate ones year-to-year. Supposedly the determinate ones die after the fruit ripens. Indeterminate varieties DO keep growing also, so keep it pruned down. As far as tiny tomatoes, Isis Candy is really good, and I have also grown Matt's Wild Cherry, which is supposedly THE sweetest cherry tomato. I have a chocolate cherry tomato going now. When you buy plants or seeds, just check to see if they are indeterminate. Same holds true for the larger tomatoes. Anything that tastes good and says "indeterminate" on the tag will give you years of gardening pleasure. They will fruit less and less as the years go on, and although I once had a 6 year tomato plant, it didn't give many tomatoes by that time, so it went to the compost pile (which then sprouted about a hundred volunteer plants!).
Cheers!
Carolyn