Hi. Welcome to Atheist Nexus from one ardent atheist to another (check out My Profile and you will see).
I have been running a busy discussion group here since September 2008. It is called "Origins: Universe, Life, Earth, religion....etc".
Do try visiting and joining in. Terry (Oxford).
Welcome to Atheist Nexus, Ashley! Two groups I can think of here that would enjoy hearing about your documentary are Atheist Cinema and Parenting Little Heathens. If you have the time and energy, I suspect people would also be intersted in hearing about it on the Discussion Forum.