In regards to this page http://rockpiles.blogspot.com/
I thought you might find them an interesting read considering your blog (which I've only just found).
(PWAX) I strongly recommend that last link. It is much more detailed and convincing that there actually is a Mayan presence in Georgia. Of course, let me be the first to say, that things like small flat topped pyramids in Fitchburg might have a connection to those people as well. The only problem I see with the argument of Mayans coming directly to the eastern US, is that so many cultures between Mexico and the eastern US have the same kind of arrowheads as the Maya - so it should be viewed [I think] as a continuum from Mexico to here.