I have to fight the same battle. You could try to raise your tomato bed, and put hardware cloth (cages in the ground, and then lay the wire cloth on the top of the bed as well. Also try cutting the bottom out of a used plant container, sink it half in the ground and half out, and plant the tomato inside that.

I read that chipmunks eat tomatoes to get a drink of water. Maybe they would leave them alone if you placed a birdbath bowl on the ground near the wooded area or where they are living?

If you find a fool proof plan, PLEASE let me know - okay?

A dedicated black snake or any of his non-venomous brethren would take care of your problem. If you can provide the right conditions (and that ain't hard if you have food available) they will stay around until the food source is exhausted.
But I have to ask: what is wrong with your cats? My chipmunks never get many generations going. Too many feral cats around here. My cats are fixed, but they do have a cat door to go outside. But I have never lived in an area that did not have enough cats to control the rodents.

There is only one cat around here that I've seen. He is a pretty good hunter, too, but the chipmunks far outnumber him. I can't keep cats because we have cat allergies, and we have two cat-hating dogs. The dogs do catch some of the chipmunks and voles, but not enough, and they are fenced out of the vegetable area, so it is totally unprotected since the neighbor's cat won't go in our back yard at all because of the dogs.