You can learn more about shamanism from these books and websites:
The Way of the Shaman (Reissue), Michael Harner. HarperOne, 2009.
Cave and Cosmos, Michael Harner, North Atlantic Books, 2013.
Soul Retrieval: Mending the Fragmented Self, Sandra Ingerman. Harper/SanFrancisco, 1991.
Welcome Home: Following Your Soul’s Journey Home, Sandra Ingerman, Harper/SanFrancisco, 1993.
The Journey (Reissue), Brendan Bays, Atria Books, 2012.
Drumming CDs, Drums, Rattles and other Shamanic Tools:
FREE Song ! Awaken thou Dreamer
FREE Poem ! The Circle