Don--I have heard 7,000 to 10,000 here state side. I don't have a clue to the accuracy of that estimate. I do know that I sale rock and points to folks in pretty much every state, annually so I am guessing that the number is fairly high. I would be willing to guess that there at least 120 knappers in most every state, if not more, so the total goes up fairly quickly.
It is for this reason I think it would be pretty neat if we could have a national knap-in, somewhat centrally located here in the US. Could you imagine all the rock, points, fun and lies. It would be a blast!!!!
Kinley