Yes, I know of a great place to find them. In fact, I bought 3-4 different maples and a ginkgo from them last spring, and I have to admit - all were in excellent condition and are thriving. I just completed my first year with the Big Tooth, and I can't wait to see how it responds in year 2.
Interestingly, it held onto its leaves later than my red oak this winter. The fall color was unspectacular, but I attribute that to it being stressed and somewhat withered after its first summer on its own.
The proprietor indicated to me last spring that he may stop carrying Big Tooth Maples due to a lack of demand and it being very slow growing in comparison to other maples. I hope that's not the case. http://www.metromaples.com/