How do I keep track of books and other references?  In digital lists, which contain items that look something like this:

1. 
ITEM CITATION (as appearing in a standard bib, whatever format I feel
like, probably an amalgamation of APA and was it ALA we did in high
school?)

Who owns it -  Me?  Which library did I borrow it
from?  Who can I get it from?  Have I seen it, or just heard about it? 
From whom, and are they important/superknowledgable?

What the
book is generally good for; my own description.  (Now I'm ready to
assemble an Annotated Bibliography, which if I ever encounter one in
other people's work, gives them Major Brownie Points in my opinion of
them.  Annot. Bibs save major academic time.)

a.  Image/quote 1
= Images and quotes that I think I need, along with the point I'm
trying to make when I need them.  Because Very Frequently the axe you
think you're grinding at the beginning of the process turns into a
Kitchenaid mixer by the end of the thing.  I find I need to be reminded
of what my original point was.  Page or figure numbers of said images,
so you can find it again.
b.  Image/quote 2
c.  Image/quote 3

2.  NEXT ITEM CITATION
Owned by
Whas' it good for
a.  Image/quote 1.
b.  Image/quote 2.
c.  Image/quote 3.

You
do this process enough, and it becomes 'dropping breadcrumbs so that
someone else, or a future version of you, can follow your mental path
and replicate your results.'  Just like science experiments.

I
wish I could throw up a real life example nicely organized like this,
but these things tend to exist in fragments littered throughout my
computer, and that distribution tends to HELP my creative process
rather than hinder it.  I've tried to line them all up neatly in one
place, and that is a useful exercise during part of the process.  But
it's also incredibly wonderful that I'll be doing something else
completely unrelated, stumble over one of my bits from a new point of
view, and that yields very rich insights that I've learned I can't get
merely by trying harder.  Fortunately the 'search' function on Windows
seems to be getting more powerful.  I try not to keep paper copies of
research unless it's part of a bound book, because my paper filing
performance is not as powerful as the 'search' function.  Someday
I will have a Fujitsu ScanSnap and it will make me very happy.

I hear
that Microsoft has a program called EndNote that will organize your bib
stuff for you, and republish in whatever format you need it to be, for
whatever picky journal editor you need to please.  I don't have it,
because I don't have to do that for my job.  Mom does, and does. 
I wonder if it has all the fields I would want – my master's thesis
used dance films, books, articles, maps, DOT charts, building
construction drawings…I do use Microsoft's OneNote, but not as well as I would like.

And all of this, by the way, is what
one goes to a thesis-writing graduate school program to learn.  Which
they don't actively teach, really, but by the time you write the book
and defend it (read: reconstruct it) umpteen times in real life, and
then once in nerve-wracking ceremony, you figure it out.