Hardwood:
Our church is doing same thing. We're a little bigger which means we have about three more people with similar concerns, lol.
I subscribed to
www.christiansecuritynetwork.org they have lots of good tips. There are others as well.
Are you in Lincoln? as chair of the committee establishing a security plan let me know I'd be happy to visit with you over coffee or even invite you to our meeting sometime. We're also looking at a full list of issues, child snatching, medical and weather emergency, building security etc.
A CCW instructor in Lincoln periodically gives an "advanced CCW class" tailored for church security.
To answer your question about a policy, I've heard lots of ideas about how to deal with it, from a sign in the parkinglot and by the front door saying "Armed security may be on premises at any time" to a letter to members saying essentially the same thing, to a note in the corporate minutes saying "armed security is authorized". The last thing we want to do is alarm people that we're expecting an incident. However you handle it, make sure it doesn't frighten people. Pastor may want to preach a sermon or two on self defense (Jesus had to tell his buddies to put their swords away so we know they were concerned with defense) and teach that turning the other cheek doesn't necessarily mean that you line up and let some deranged idiot who can't get a date start shooting at you.
I've already heard that some churches have authorized "any regular member" with CCW to carry (once the law goes into effect) and others are being a little more selective authorizing only certain members.
One thing you might want to consider, what will your insurance do if you authorize CCW? I'm not saying call up the insurance company and let them know you're expecting the OK Corral to happen on Labor Day, but you might want to consider what they might do, including drop coverage.