Washington Irving is actually buried in the Sleepy Hollow cemetery.
And you could visit, were you in upstate New York.
Furthermore, the churchyard described in The Legend of Sleepy Hollow is an actual place which still exists two centuries after the story was penned, and would be worth a visit as well.
Please see the attached link to the Poughkeepsie Journal.
Poughkeepsie Journal article on Washington Irving's Final Place of Rest