Hey Wile.E, I commend your efforts. I suspect this list is more or less endless, but two key authors I've come across are Weston La Barre and Barbara Myerhoff, a reference list would not be complete without them (e.g. Myerhoff: Peyote Hunt: The Sacred Journey of the Huichol Indians (1974); La Barre: The Peyote Cult, 1938 - one of the most important early works). Also, consider Schultes 'The Appeal of Peyote (Lophophora Williamsii) as a Medicine', 1938, to add to his others.