I'm in the Mid-Atlantic!
It will take some time to get this together. I think first and foremost, communication with each other is key to getting something started. We're all very spread out, and so communicating via e-mail, and sharing interpretations and such on youtube, will only help.
I'm a member of the Historical European Martial Arts Alliance, and I will ask them about people that might be interested in the archery aspect of martial arts, and how to help us become an organization. Once I get my bow again (alas, it is in storage several states away!) I will also get out and practice, and see if anyone else in my area is interested in getting together and starting a local group.
I'd basically want to see the AWBS ultimately as an umbrella nonprofit organization that aides diverse local practice groups with resources. Resources on how to shoot war bows, resources on how to make war bows, resources on the history behind what we do, etc. And of course, communication and hopefully, competition between groups.
So the first thing any of us can do is see if we can start a local group. It doesn't have to be official (just legal hopefully), but getting some friends together and practicing once or twice a week does wonders to help improve.
And since we aren't necessarily limited to only practicing the English/Welsh war bow, we might be able to get people interested in other national styles of martial archery to practice alongside us. I don't think there's anything wrong with "cross training". In other martial arts (I want to focus on archery as a martial art, not just a competitive sport), all it does is make you a better martial artist as you learn about different styles and different ways to solve the same problem. I don't see why that can't apply to archery as well.
I'm going to work on some essays/statements on some of my ideas for this in the next couple of weeks and send it to you all on the e-mail list. Stay tuned!