This question is long, but important, perhaps the first of many.  I
hope to give someone who has considered it at length in the past an
excuse to share their findings.  Where a compromise must be made for
brevity's sake, please provide breadth rather than depth in your
answer.

Consider this scenario: most of the people in your county/city are
gone {dead, fled, evaporated}, and a small group remains, hoping to
restore order and functionality to the civilization they love.  All of
the elements needed to maintain their civilization - factories,
supplies, conduits - remain, though they may need repair and
operation.  This group needs direction --

  ! reminders of the many foundations of everyday life which require
regular maintenance, and the layered methods for maintaining them
  @ reminders of the many skills that must be learned before they are
required to cope with a breakdown or disaster (natural and social,
periodic and random)
  # pointers to resources (multiple sources of books, physical tools
and locations; relevant professions) for the above
  $ efficient resource-chains for attaining critical goals [a
soup-to-nuts chain of books, tools, supply chains, and organization
needed to grow modern crops under various adverse conditions]
 
Two parts to this question:

 1. What organizations, current and ancient, in all parts of the
world, have attempted to prepare for this scenario?
 
 2. What has been written about this subject?  This includes fiction
[even as applied to society at different stages of development],
practical overviews of technology/modern life, Histories of
civilization, and broad contingency plans [government or
organizational documents].  Again, both current and dated writings
apply.