The following sources are those I found most useful while researching and preparing the Building Utopia: Bhagwan Shree Rajneesh podcast series. I mention specific sources on the page for each episode as well.
Books
Sheela Birnstiel, Don't Kill Him! The Story of My Life With Bhagwan Rajneesh
Lewis F. Carter, Charisma and Control in Rajneeshpuram: The Role of Shared Values in the Creation of a Community
Frances Fitzgerald, Cities on a Hill: A Journey Through Contemporary American Cultures
Vasant Joshi, The Awakened One: The Life and Work of Bhagwan Shree Rajneesh
Hugh Milne, Bhagwan: The God that Failed
Jane Stork, Breaking the Spell: My Life as a Rajneeshee and the Long Journey Back to Freedom
Kate Strelley, The Ultimate Game: The Rise and Fall of Bhagwan Shree Rajneesh
Articles
The Oregonian's 1985 Investigative Series on the Rajneeshees (20 parts)
The Oregonian's 2011 Follow-up Series on the Rajneeshees (5 parts) by Les Zaitz
The Rajneesh Times, 1981-1985