Hi,

Whenever you're doing research prior to 1850, the convential approach won't work because of lack of information on the Census records and the lack of Census records.

FamilySearch is a good alternative to finding older information. Go to www.familysearch.org
Click on Catalog
Enter New York, Rockland
Search

and a list of possibilities are listed. I clicked on Biographies and there are a couple of books that have biographies of early settlers. Successful Searching!