Automatic writing is possible when a spirit finds a person who is susceptible and who is aware of the spiritual world. This is a comprehensive list of sites, exploring and explaining this phenomenon.
A record of automatic writing from The Starters and from The Auroral People. Addresses, among other things, the meaning of life and life after death. http://www.geocities.com/glfeltmate
Introduction to higher self and spirit guides through automatic writing. Tatiacha includes a meditation script that you can record as well as pertinent questions to ask once you establish contact. http://www.spiritnexus.org/tools/automatic.htm
Since the early days of Spiritualism, automatic writing has been accepted as a way for trance mediums, and sometimes ordinary people, to receive communications from the spirit world. http://www.prairieghosts.com/auto_writing.html