Hey Paul,
Hope I'm not out of line here but you seem to be about where I was
10-12yrs ago.
I bothered lists and forums across the 'net learning my way around but
what was most helpful to me was face-time with knowledgeable folks.

To that end I would suggest the recently resurrected Northfield linux
users group (norlug).
They meet weekly at the Hideaway in Northfield- coffeehouse coders- and
are starting technical meetings this month. First one is on Raspberry
Pi.

http://www.norlug.org/

Certainly not trying to dissuade you from posting here just pointing
out another helpful option for your quest for knowledge.

harv