After you mention his death in the biography section, then write another sentence about where he was buried and state your source.
Yes, books are acceptable sources. If you have some opinion about the book's reliability, you could state that in the footnote. Your sentence above beginning "The book was written in 1951..." would, I think, be a helpful addition to a footnote.
Yes, your book excerpts seem appropriate.
Profile looks good. I wonder if you could find a census listing to strengthen the record?