You should take a look at the book, America B.C., by, Barry Fell. It has a LOT of information about the Ancients in North America. Includes a lot of symbols and their meanings.
For KVM's books, he said that his Treasure Hunters Manual #6 was the better of the 2 (#6 and #7). Other excellent books he published that should be in everyone's library are, Sudden Wealth written as Deek Gladson; The Encyclopedia of Buried Treasure Hunting, by KVM; Waybills to El Dorado, by KVM. You might be interested in his 2 books about how many folks have made their living while traveling around treasure hunting. They are Owl Hooters' Manual No. 1 and Owl Hooters' Manual No. 2, by KVM.
Just as a point of information, Dean Miller, aka Karl Von Mueller, wrote that the way he came up with the pen name, Deek Gladson was that he'd taken his wife's maiden name of Gladys Deekson and rearranged it to produce "Deek Gladson". He also copyrighted his books, later on in the name, Gladys Miller, as insurance for his wife's financial future should something happen to him.
One last point. His book, Waybills to El Dorado, is the one that got some folks really upset with him for giving away so much important information on many proven treasure leads. He believed that someone of that group was responsible for burning his outbuilding that held his office with all of his research files. That particular incident was a major factor that lead to his declining health. The ba$tards who burned his place were responsible for his death, in my never humble opinion.