Could I ask a few questions to help with the research:
1.You say he was from Alabama, was he buried there also? 2. you mentioned his gravestone, what is the name of the cemetry, town, state. 3. Do you know any of his parents or siblings names? 4. Was he White, Black, Indian or first generation immigrant? 5. I take it that he was married and had children, since the family line is in the present, what was his wife and childrens names. 6. he may have been in the merchent navy (civilian), during the war, if not a veteran ofthe US Navy. 7. the town he is buried in must have a library or museum, or even a town clerks office, where you can look up around the date of his death for his obituary, even the cemetery might have some basic records of internment. 8. what are the last names of the stones next to his, most people are buried around relatives in plots, unless if in a private family cemetery which of coarse is better for finding family members! any ifo to add for questions 1-5? 6-8 are just somebasic research suggestions I use often, good if your in the same location as the gravesite.