American cemetery records have been very well researched and can be searched online with comparative ease.
Many provide details not just of the graves themselves but local historical information as well.
Many people who emigrated to America in the C18th and C19th were buried together in small plots and these make for interesting investigation
Anyhow, to help kick off your research, the following list of sites with their attendant links should be very useful in tracking down that burial site
Interment.com an excellent site to start with
Cemetery Junction has an alphabetical list of hundreds of cemeteries, many have been transcribed by individuals so it can be a bit hit or miss but some very good records
A big hurrah for a chap called Allen Wheatley Cemeteries Photographed, who has done a tremendous job of photographing individual headstones, his site is hosted by Rootsweb but thank you Allen, a great service.
Another good listing site cemeteries
To search for Civil War burials Civil War Soldier Search is a very comprehensive site