TG -
There are a lot of methods for saving tomato seeds, plenty on the web if you do some Googling. The way I have always done it and with good success, is to select tomatoes that are over-ripe from my best plants. I lay out 3 or four thicknesses of newspaper, write the variety of tomato in ink on the top layer in a spot near the edge, cut open the tomato and squirt out the seeds onto the newspaper. I spread the seeds out into a single layer, pulp and all, and put the whole thing in a spot where it can dry undisturbed. In the past I used to set them out to dry in the tool shed, which warmed up nicely during the day. This year, they are lying on shelves in the greenhouse and are drying in a day or two. Once the seeds are thoroughly dry, I either scrape them off the newspaper and put them in envelopes or sometimes I just roll them up into the sheet of newspaper they are drying on. I make a little packet out of the newspaper, seal it with a piece of tape, and write the tomato variety on the outside. I store my seeds in a plastic box with a lid in a dark place in the garage attached to my house. They stay cool and dry, it doesn't freeze there. The percentage of germination for seeds saved this way has been very good.
Tomatoes are one of the easiest plants that you can grow from seed, don't be afraid to try it!
Terri in Indiana