Just when you think you know all you can know about a geographical area, something comes along and surprises you. Paul Friday has transcribed and published a series of death records which I was unaware of: Deaths & Burials 1780-1806 Reverend Curtis Coe's Records for Durham, New Hampshire, New Hampshire Genealogical Record 27 (2010):11-26. These records were part of the Rev. Coe's personal papers and filed in the Coe/Burt Papers in the manuscript holdings of the New Hampshire Historical Society. No one knew of this resource, not even the editor of the Record, who is an esteemed genealogist (and I think one of the best).
So this is a good example for two things: (1) If there are no records for town or church, follow the ministers. Find where their personal papers went. (2) Historical societies, libraries, genealogical societies, etc. must produce detailed finding aids to their manuscript collections and put them online for search engines to find them. Who knows what other gems are out there.
Sadly, all my Durham ancestors lived there from 1650 to about 1760. By 1780 they were in Barrington, Madbury, Rochester, New Durham, and elsewhere.