Several sites exist to help you find the cemetery and tombstone information of your veteran ancestor who died during wartime and at home.
The United States Department of Veterans Affairs, Nationwide Gravesite Locator has a nationwide grave locator to help you search for the graves of veterans and their family members in VA National Cemeteries, state veteran cemeteries, and other military cemeteries as well as for veterans buried in private cemeteries with a military headstone. This web site also includes other information such as obtaining a military headstone or Presidential Memorial Certificate and military funeral honors.
The American Battle Monuments Commission, American Battle Monuments Commission, is responsible for the overseas cemeteries and memorials that honor those who have died while serving in the United States Armed Forces. An online database provides information about those buried in the 24 cemeteries located on foreign soil. Soldiers listed in this database include those from the Mexican War, Civil War, Spanish American War, World War I, World War II, and the Korean War. Additionally, the Commission has a database of all interments at Corozal American Cemetery in Panama, which includes civilians who helped build the Panama Canal. You can search by conflict and then by name.
Sons of Union Veterans of the Civil War, Sons of Union Veterans of the Civil War, originally an auxiliary of the Grand Army of the Republic, have a web site that includes a National Graves Registration Database that includes information about Union soldiers gravesites. Information includes the person's name, birth date and death date, information about military service, cemetery buried in and location of gravesite, military headstone or markers, and the GAR post that the person belonged to. Additional information may also be included in a section entitled "misc. info."
Casualty lists also provide researchers information to help locate the death of a soldier during war time. The web site, Access Genealogy, http://www.accessgenealogy.com/worldwar/, includes digitized images of World War II Casualty lists for the Army, Air Corps, Navy, Marines, Coast Guard, and POW's. The lists are organized by state or territory and then by county.
Ancestry.com's military database holdings also include casualty lists. The World War I, World War II and Korean War Casualty database, http://www.ancestry.com/search/db.aspx?dbid=8853, is a partial listing of the American Battle Monument's Commission's database. They also have a database entitled, the World War II and Korean Conflict Veterans Interred Overseas, http://www.ancestry.com/search/db.aspx?dbid=4283. This information comes from the National Archives and Records Administration.
Casualty Lists are available through the National Archives web site. For Korean and Vietnam War Casualty see http://www.archives.gov/research/korean-war/casualty-lists/. Additionally, the World War II Honor List of Dead and Missing Army and Army Air Force Personnel at http://www.archives.gov/research/arc/ww2/army-casualties/index.html and the State Summary of War Casualties from World War II for Navy, Marine Corps, and Coast Guard Personnel at http://www.archives.gov/research/arc/ww2/navy-casualties/index.html. These are arranged by state and then by three categories; dead, wounded and released prisoners.
For more information on the history of Memorial Day check out http://www.usmemorialday.org and the About.com's Women's History site at http://womenshistory.about.com/cs/holidays/a/memorial_day.htm.