I guess I see many people not being ready for the purely anthropological material. Portions of the nuts-n-bolt anthropological procedure can be culturally or environmentally specific. An example of a anthological approach would be to take plant X, prepare with method Y, and consume under conditions Z. Extending the hypothetical example, to know that the native tribe X holds red leaves with purple flowers above their heads and dances counterclockwise does not help the Western reader. Exploration of native customs can lead to diverse views. Some are contradictory. In the world of Carlos Castaneda the allies of the Shaman are to be forcibly tamed. Other cultures promote the gateways of substances to meet the allies. The Western style of Michael Harner promotes going on a drum journey and meeting the guides in a relatively peaceful way. Which one is right? They all are.
I guess my thoughts are going in the direction that "self-exploration" books are valuable. They are not for everyone. For a time I read many "self-exploration" books - stories about other people's shamanic paths. I've tired of reading about how other people have walked the path. At this point I am much more likely to read a self-exploration book. Another style of book I've very much enjoyed applies shamanic concepts to topics of reality (quantum mechanics) and healing. Actual shamanism is mentioned, showcased, but these books are not about the "nuts-n-bolts" of the practice.
Read the books that appeal too you. It's a good thing when it connects to you.