I know your message is old, but I wanted to put this information here in case you, or others, would find it useful in the future:
There are loads of great resources for 12 step programs on the aaagnostica website, I love their reader Beyond Belief, it is incredibly helpful to my recovery.
I'm an atheist and a compulsive overeater.
The higher power that the program hinges on is still tough for me sometimes but my higher power is the collective wisdom and experience of the OA fellowship. As a group they are undeniably stronger and have more experience and ideas than I could possibly have as an individual. This community is where I seek the energy and guidance for my recovery.
One thing I have found to be a total lifeline is having an atheist sponsor. They are not easy to find, but without one I would have seriously struggled with staying in program and overcoming my initial frustrations (some of which persist, but the rewards I've gained mean I understand that OA really works for me and encourage me to stick at it).
There is a freethinkers group I co-ordinate on yahoo under the name '12step freethinkers anonymous', this is a place for atheists, agnostics, and freethinkers to come and connect with others in the OA community who might be having similar issues with the Higher Power aspects of the program, or to share how they've successfully worked those elements.
I'm hosting my first skype meeting this Tuesday, 26th May 2015 (it'll be on Monday 25th May in the evening if you're in the USA). You can find it if you search skype for 'OAfreethinkers', the call is audio only and newcomers are welcome, all are welcome in fact! Hopefully I can get some members involved and make the meeting a regular thing.