Right before a deep freeze, pull up the entire plant, tomatoes, roots and all. Don't worry about leaving dirt on the roots, but make sure the entire plant is whole. Put the tomato plant in a sheltered place like the garage. Over time, the green tomatoes will continue to gain nourishment from the plant and will continue to ripen to red. You should be able to extend the 'garden tomatoes' in your cooking repertoire for another month or so. This works not only with regular garden tomatoes, but with grape, cheery, and pear tomatoes too.
Since I am sharing a picture of some of Dad's and Alma's beautiful tomatoes, I thought I would share a few pictures of their garden as well. Dad has built several of these gated gardens to protect their plants from deer and raccoons. Each raised bed is made with treated lumber and is wrapped with wire mesh. The areas within the raised beds are soil enhanced with compost that Alma creates with household scraps. I like the compactness and orderly appearance of their raised garden beds. Because things are planted close together, weeds don't have much room to grow, thus ---- less work!