Mr. Completely linked to an article at Confederate Yankee here, on the subject. Nice piece of work, that also ties in with something Kim took time to post.
One of the things that comes to mind in this is that preparing for trouble doesn't have to cost a fortune. Canned/dried food is fairly cheap, so is bottled water. A good first-aid kit isn't too bad. And good guns for the subject don't cost a fortune.
I was at a gun show today/more later/ and among other things saw that you can buy a 59/66 SKS for $125 plus tax. 500 rounds of Wolf or other ammo can be had for $45-$55. Handguns are going to be higher for a good one, but a good-condition used .38 or .357 Mag revolver can be had for between $200-$300; some good semi-autos aren't much higher. And practice ammo for many handguns can run as low as $4 to $9/box; good defense ammo will cost more, of course. Shotguns? You can find a decent pump for anywhere from $150 up, depending on brand/features, and ammo for it- unless you're getting the gold-plated slug ammo- isn't bad. Thankfully, with modern ammo a cleaning kit can be very basic and do the job(note: a t-shirt you don't wear makes good cleaning patches).
I've known some people who flat would not take preparing for something like this seriously, because it scared them to think about it. It's not, after all, a pleasant subject. But it's one that needs to be considered.