The
RPG etc will be available for shops to stock if they choose to do so
(here's some of their last
RPG project in the wild
http://www.waylandgames.co.uk/1618-achtung-cthulhu)
as to when they'd get to stores take the estimated
KS release date and add6-9 months at least, and that would be for the main book and maybe one or two of the others,
expect the rest to trickle out piecemeal after that as I would not expect a stores to want to order a huge pile of new books for a brand new game at once