forgeblast
Elite Member

homedistiller.org has some nice plans
Emergency Water Kit has the same ceramic filters that the berkley has but you put them in a 5 gallon plastic bucket and save bout 200.00 over the berkley.
Pool shock is also useful.
As far as people not being fully self sufficent. I would think that if you were able to model your situation on a monastary, you might get really close to being self sufficent. Some monastarys are self-supporting meaning they trade for things they need, which after (I Feel) an event is what most places will gravitate to.(I hope).
"Whenever possible the monastery should be laid out so that everything essential, that is to say water, mills, garden and workshops for the plying of the various crafts, is found within the monastery walls."
Monastery Gardens: Ancient Herbal Folklore - Yahoo! Voices - voices.yahoo.com
Its a lot of old "tech" that you would need, but if you had the time and drive it could be done.