i'll have to look up the web page where i read about making acorn flour,
actually, the processing isn't that involved, no more so than cooking.  as i
recall, the indians who used  the acorns would grind them up, then put the
acorn meal into a bag and leave the bag lying in a stream or river for a
day.  the cold running water would take the tannins out of the acorns.  then
just dry out the meal, and use it.
i will check, and get back with details.

JoAnn.