The Simon Necronomicon is a purported grimoire written by an unknown author, with an introduction by a man identified only as "Simon" a possible alias of Peter Levenda. Materials presented in the book are a blend of ancient Middle Eastern mythological elements, with allusions to the writings of H. P. Lovecraft and Aleister Crowley, woven together with a story about a man known as the "Mad Arab" (itself derived from several stories by Lovecraft).
The book was originally released in 1977 by Schlangekraft, Inc. in a limited edition hardback printing, followed by a paperback release by Avon Books, and a subsequent paperback release by Bantam Books.
Levenda did acknowledge working on the book with Simon. Ian Punnett made a reference to interviewing "Simon" and mentioned similarities with Peter Levenda and asked Peter to "say hello to Simon for him, next time he saw him", to which Peter laughed and said that he would.