Movie filmed on the grounds of the Glensheen mansion:

"You'll Like My Mother" starring Patty Duke (1972). 

Books of interest related to Glensheen mansion tour: 

"Glensheen's Daughter, The Marjorie Congdon Story" by Sharon D. Hendry (1998).

"Secrets of the Congdon Mansion: The Unofficial Guide to Glensheen and the Congdon Murders" by Joe Kimball (2002).

"Will to Murder: The True Story Behind the Crimes & Trials Surrounding the Glensheen Killings" by Gail Feichtinger (2003).