[GpsFrontier]

I haven't tried grafting, or really even gave it much thought. But I found a few links about grafting tomato's;

Grafting Techniques for Greenhouse Tomatoes
Grafting for Disease Resistance in Heirloom Tomatoes
Grafting Tomatoes for Production in the Hot-Wet Season
Tomato Grafting Project (How to Video)
Tomato Grafting Project