"Rush to Judgment" was one that I read. If I recall, that came out in approx 1966, not long after the Warren Report was released.

Another good one was "Best Evidence," with the contention that the Parkland surgeons and coroners altered JFK's body surgically in order to conceal that there was a frontal headshot.

Did anyone read "JFK" by Fletcher Prouty? He contends to be the basis for the "X" character in JFK (portrayed by Donald Sutherland). That was interesting, if nothing else. He makes a lot of claims, but there are not too many who can dispute or support those claims based on his classified work within the intelligence community.