Cemeteries of Warren, Washington, and Saratoga Counties (Flickr sets from dmcordell):

Cemeteries & Graveyards & Tombs (Flickr Group)
"Photos of cemeteries, graveyards, tombs and headstones of any kind, shape or size in colour, black & white or sepia...Please remember all of these groups are family friendly which means:
- and so on..."

Graves of Veterans of the American Civil War (Flickr Group)
"This group is dedicated to photos of the tombstones, headstones, and graves of authentic veterans of the American Civil War; 1861-1865. All are welcome, Union or Confederate, the good or the bad, as long as they served in some military capacity whether it was volunteer, conscript, or contract. All are welcome to join and submitting photographs is not required. Discussions are intended to add to the history of the veterans. Almost all photographs will be accepted; non-photographs will be evaluated on a case by case basis. This group is for non-commercial educational purposes.

This group is open to children under eighteen years of age thus no pornography is allowed. This pertains to the group photographic pool, discussions, and member icons (both icon image and text). Also do not bring politics into our group.

Since search engines only 'see' text and not photos, it is preferred that the words on the grave markers be entered as text with the photo. However this is NOT REQUIRED." -David C. Foster, Group Administrator

*The Revolution Flickred 1775-1783 (Flickr Group)
"The American Revolution of 1776 ~ Please post "SafeSeach" only photographs pertaining to America's revolutionary battle for liberty that transpired between the years 1775 and 1783. If not readily apparent from the image, descriptions and other pertinent identifications of your photograph will be much appreciated, especially the location, dates and the person or historic event's significance. Six Photos Per Day!"
*includes photos of historic sites, reenactors, etc. as well as cemeteries and headstones

A listing of other Flickr Groups with the tag of "cemeteries" can be found here