He has written several technical books relating to diving, as well as extensive documentation of the shipwrecks of North America.
He has also published a number of futuristic fantasy fictional works, although none of these have been a notable commercial success to date.
The publication of the 2004 book Shadow Divers,[5] a New York Times bestseller, brought a huge amount of publicity to the North East American wreck diving community, and turned the two divers featured in the book, John Chatterton and Richie Kohler into media stars.
Gentile's book divided the diving community between those who regarded it as a cheap shot, motivated by jealousy of the fame which Chatteron and Kohler had enjoyed as a result of the book, and those who believed it was a fair attempt to set the record straight and ensure that credit was given to others who had played a key role in identifying the submarine.
[8] Gary Gentile served in the 25th Infantry Division during the Vietnam War where he was severely wounded.