Homegrown tomatoes are one of my favorite foods, but unless you grow them or have a good friend who does, you have to rely on grocery stores. Farmers' markets and roadside stands can be good sources when in season. In January, be very suspicious of a "vine-ripened" tomato. During cold-weather months, I rely on cherry tomatoes to get my fix. It's hit or miss, but they can be much sweeter than the larger varieties.