No worries man, here to help!
1.
Well it's hard for me to make a suggestion for one book only because there are quite a few. The list below are ones I have personally used and have got some value from for human figures. You might want to go and have a look to flip through them and see if it is what you are after.
Andrew Loomis - Figure drawing for all it's worth,
Drawing Head and hands
Stephen Rogers Peck - Atlas of Human Anatomy for the Artist
George Bridgman -
Complete guide to Drawing from life
Everyone raves about Bridgman's classic books on constructive anatomy. This is a compilation of them all. I never used them that much myself, but there is a lot of good in there from looking through.
Frederic Delavier -
Strength Training Anatomy
This one is a bit different. It is actually aimed at body builders, not artists, but the detailed drawings of the muscle groups and how they attach to the skeleton are great. If you want specific musculature reference, it is great. All the figures are of very muscly men and women so it isn't good for a direct one-for-one use, but more an understanding of placement and movement based on the exercise movement so one gets a sense of how they appear under different motions.
My personal favourite for anatomy is Glenn Vilippu's lecture dvds. The problem is the full set is very expensive. I got lucky and got copies off a friend. They are actual classroom lectures and so sometimes very sleep inducing, but I really liked his approach for figure construction and he draws through his explanations which you don't get in books. He has books too, but I'm not sure how good those are.
Nothing beats just practicing a lot at life drawing, or Croquis Cafe (youtube) or using pose sites like pixelovely.
2.
Ha ha. It is amazing what a picture can communicate when some thought goes into it.
I am coming to realise that the "why" of a piece is more important than how technically good it is.
It all definitely matters for sure, but if there is no emotional impact in the viewer, if there is no reason for the piece, it is ultimately forgettable. Many artists seem to swoon over immaculate technique and things looking pretty or perfectly implemented, but the lasting impact of a piece that stands the test of time will more be governed by the emotional content it arouses in viewers than how well drawn it is, in my opinion.
3.
Ahh I see. In this case, find appropriate reference then do separate short studies to learn about the subject,
then apply what you learned to your piece. This is the way most will suggest you build up an illustrative piece. It definitely has its merits.