Here we are in mid August, and I'm still buying tomatoes from the store or the Farmers Market. I planted some tomato plants, but the deer seem to have developed a taste for them, and they've been eating them just before they are ripe enough to pick. I tried dusting them with red pepper, but it's been raining so often that it just gets washed off. Might have to resort to harsher methods...
I can remember my grandfather saving seeds from his tomatoes and many other plants. I don't ever remember him buying any seeds or plant starts, but he and his friends would exchange vegetable seeds and cuttings.