I've read of serial number search sites that will trace a rifle if the veteran has his rifle number writen down or memorized. Some Garands have been traced and sold to the men who carried them in the service.
Heres a site with free downloads of a book detailing the manufacture processes and machinery used to produce the 1903 Springfield.
Amazingly detailed book, I've not seen another like it for any other firearm. A terrific collection of illustrations.