Just a pitch for pre-planning - do a neighborhood inventory before a disaster strikes. Find out where the doctors, dentists and nurses live, who does construction for a living and has access to heavy equipment (and chain saws, we're heavily wooded), and who the lawyers are, they will need the most help (that's not a joke). As part of my two block survey I talked to about 85% of my neighbors, and located gas and water shutoffs for 70% of them (a few didn't want me tromping on their property or to spend the time). On two of them the water main shutoff was rusted shut, and would be impossible to turn in an emergency. I recommended they contact the utility or a plumber for a fixup, and I happen to know at least one of them did. Then chart the locations (green dot for water, blue dot for gas, N S E or W of house) and keep your neighborhood map handy - I made 3 copies, in the event of a bad shake I hope to hand them out to people in the golden hour after the earthquake and ask them to quickly check for water or gas leaks and turn off those at risk (yes, I also start with 4 giveaway wrenches). The State of Washington actually encourages this inventory using a FEMA grant, it took all of a weekend afternoon and I got out and met people I'd never seen before.

Big advice: don't ask about guns, kids, preparation, or anything too personal - there's no need, and its none of your business. Anyone coming to your door is usually looking for money or for something from you. I always left behind a flier with a description of what I was doing and where I lived, which is right nearby. If I were to do this again further away from my home I would definitely precede my visit with a door hanger that said I would be walking around on x afternoon doing an inventory. And I think this would be a nifty project for a Boy Scout troop doing their emergency preparedness merit badge. But a 2 block radius is about all I could handle in a disaster.