One of the most "user-friendly" books on the assassination I've ever read, and the best introduction to the subject for novices, is Reasonable Doubt by Henry Hurt (1986).
A Readers Digest roving editor and political conservative, Hurt's manuscript was reviewed by Harold Weisberg and Sylvia Meagher before it was published. Hurt began his work on the subject when he received a call in 1981 from a man who claimed he had participated in the assassination, Robert Easterling. The chapter on Easterling is the only weak section of the book. He talked to the man and then decided to plunge into "the murk of the Kennedy assassination" to judge his claims. The only previous connection he had had with the subject was in locating and interviewing Marines who had served with Oswald for Edward Epstein's book Legend. He recalled that many of his fellow Marines said Oswald was physically uncoordinated, which made it difficult for him to shoot and was the reason why he didn't drive.
"During the early months of work, I fully expected that at any moment I would encounter that single, unalterable piece of evidence that left no question that Oswald was the man who killed Kennedy....That discovery never came. Instead, the evidence continued to point in a different direction...A powerful case can be made that Oswald did not kill Kennedy."
