Here are a few resources I’ve found to be valuable:
The Interface Project: stories of people living with intersex traits
XX/XY: 13 minute documentary by Porter Gale and Laleh Soomekh. The film features two people born with intersex traits. Both underwent genital surgery in infancy.
Journal of Pediatric Urology, July 2013: Milton Diamond and Jameson Garland call for a moratorium on infant genital surgery.
Brief Guidelines for Intersex Allies published by The United States affiliate of the Organization Intersex International (oii-usa.org)
Hida Viloria’s Blog: Intersex and Out