Former Bush spokesman Scott McClellan’s dad Barr who was a promenient Texas attorney pretty well lays out the case in: “Blood, Money and Power: How LBJ Killed JFK”
http://www.amazon.com/Blood-Money-Power-How-Killed/dp/161608197X
James Tague, famous for getting a fragment of concrete in the cheek caused by a bullet that day has also just released a book and suspects LBJ.