Do you want to get a good deal on GeoTrax...have you tried http://www.craigslist.org. If you are unfamiliar with it, it might not look like much at first but this is a great and free classified ads system.
Choose the State and then City in which you live, then off you go. Try a number of different search terms individually as many people are less careful about the keywords they use in their ads.
I suggest trying things like geotrax, geo trax, geo tracks, fisher price train and any others you can think of.
They also give you an RSS feed that you can plug into your favorite RSS reader so you will notice right away when new items are posted.