Cannot think of a better "quick" course/reference on piloting for sailors than the US Sailing book on the subject. Many others focus extensively on powerboat situations, where a compass correction error of 2 degrees can put you way off target after a half hour at 25 knots. Sailors are more concerned with the effect of spending hours in current, or changing wind directions, which are more easily compensated for on powerboats. US Sailing''s book is succint, pretty complete, and uses good examples that are relevant to sailors. It''s also not too expensive. Check their website for more info. Celestial, if you''re into that, is another issue.