During the Depression-era of the 1930's, the Works Progress Administration hired workers to survey the cemeteries in the U.S. to list burials of military veterans. In Indiana these records are in hard copy in the Indiana State Archives.
Archives unpaid volunteers are indexing these records and putting them on the IndianaDigitalArchives website. I noticed that the Marion County lists are now up and running. Take a look to see if any of your folks are listed. Many cemetery headstones have disappeared between the 1930's and today--maybe a few surprises will come your way. [Still no images...sigh!]