If you know the town, county, and state that your grandfather died in you can request a copy of his death certificate "for geneology" purposes only from the clerks or registras office in that town or county which ever way that state works it.Make sure you don't ask for a certified copy, that way it shouldn't cost you too much if anything at all. Some states give it to you free. When you call they will tell you what to do and if it costs anything. Get his social security death index info. off line if you belong to one of the websites like this one or ancestry.com. Include that with a letter, and a self-addressed stamped envelope and wait for the mail to get back to you.