Thats cool.  I used to to a lot of arrowhead hunting along the Mohawk river.  I miss that but I have since taken up looking for shark teeth and its really fun.  The different variety of teeth added to other fossils that you can find make it a very addicting hobby.

I should have explained myself further.  I have long since moved to Maryland, and I look for teeth at the Chesapeake bay.  I think the closest area to you  would be in New Jersey. 

Nothing wrong with arrowheads, I wish they were more accesible in Maryland.  Down here the quality of the flint/chert is nothing like NY, and land is on lock down with all the posting!  The limited access is very frustrating, that also includes the bay for teeth hunting.

I have some good pix of my New York finds.  If they decide to to start a New York artifacts board I will try and post.  If you havent looked by the Schoharie river, by Central Bridge off interstate 88,  its worth a trip. 

North of that.  Check a map for Central Bridge off 88.  This is a huge valley that has cliffs over the Schoharie river.  There was a farm called "Westhiemer Farms", they gave us permision to comb their fields, loaded with things.  You could also "fish" the river and check the fields along the banks.