Hi.
A simple Google search yielded several sites which may help answer your question. Several gave the impression that he used to, and possibly still does, sign books.
He also has a Facebook page which seems to suggest that he stopped communicating with his readers a year ago.
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"Write your Life Story and Publish it" .....
"Longdon Green, Farewell"....
"Use Google's Picasa for a Kindle, e-book, cover picture." ... on Hub Pages
Use quotation marks when searching.