The Issac Van Wart who helped capture Major Andre is buried in Elmsford, NY which is just west of Tarrytown, NY (Westchester County) on Sawmill River Road (service road). The mayor of Elmsford is very helpful in locating the grave ... it's a cute town full of history. The oldest Dutch Church still having services is located next to the cemetery ... it's a small cemetery and in disrepair. Anyone who is related to Van Wart should make a donation for the upkeep. The cross street is Van Wart Street - located just south (maybe 1 mile at most) from Main St.
My father completed a geneology check on the Van Warts and from that I became a member of the DAR (Daughters of American Revolution). Anyone who needs help verifying their connection should contact their local DAR chapter. DAR is very good in helping. I live in Manhattan and the chapters here are helpful.
We traced back to 1693 when an Isaac Van Wart became an elder of Philipse Manor or the Dutch church .... I have the complete line at home.
New York Public Library on 5th Ave has a very good genealogy section.