It's been many a moon since I inhabited Twelve-Step Land, but I recall that Al-Anon followed the Twelve-Step process incepted by Alcoholics Anonymous, whereas ACOA did not have a formal recovery model (I believe some ACOA fellowships did follow the 12-Step model out of familiarity and previous experience with Al-Anon). I do recall as well that many people who weren't living with alcoholics or drug addicts (or both) still went to Al-Anon, as well as ACOA. Al-Ateen is a version of Al-Anon for the special needs of teenagers living with an alcoholic/drug abuser.
I'm a sober alcoholic, by the way. I live in the Twin Cities Minnesota area, and Minnesota is home to the Hazelden treatment facility (which by now has sprawled all over the country) as well as a 12-step fellowship approximately every block.
I think your best bet, believe it or not, would be to either hit the Yellow Pages in your area, or Google it and see if you can pull up websites for each fellowship.
HTH -
A-JOck