Tobacco and Shamanism in South America by Johannes Wilbert

(Google Books) An ethnography of magic-religious, medicinal and recreational tobacco use among nearly 300 native South American societies.
Wilbert found that South American Indians use tobacco in many ways and that a close functional relation exists between tobacco and shamanism.  Excerpt: "cigars-cigarettes prevailed over the great northern focal area of the continent and adjacent Antilles and Middle America, pipes over a roughly crescent-shaped belt peripheral thereto on the southeast, south, southwest, and west, a tobaccoless zone peripheral in turn to the pipe zone" Continued