here is a link on how to save your tomato seeds.
http://gardening.about.com/od/totallytomatoes/ss/TomatoSeeds.htm
And here are the instructions for using Oxi-Clean to save your seeds. This is much easier than the process above.
http://www.settfest.com/2009/01/saving-seeds/
Thanks. That’s a big help. I don’t think we have any Oxi-Clean but I do know that we have trisodium phosphate.