I got my seeds from the Fedco Seed CoOp in Maine. Our tomatoes here in Northeast US have only just started turning red this past week or two - that's LATE for us. I hope they hold out 'til my tomato gizmo comes in from Gardener's Supply. It separates the pulp from the skins and seeds - should make sauce day a whole lot easier. You can certainly add herbs to the tomatoes you are canning, but go easy on them.
Flavors tend to be enhanced by the processing.
Add them to the tomatoes when you heat them, prior to filling your jars, and taste-test it. If you get really interested in all this, don't forget to check out the Home Food Preservers Magazine link. It was a newsletter, and will be a magazine with the next issue. Of course, the drought and the extreme heat of this summer have been rather uncooperative. Mmmmm, green tomatoes.