One of the Best Books I have come across for learning Navigation Skills is the Manual of Map Reading ISBN 011 771905 6 published by HMSO
It's full of information such as: Basic map reading and interpretation of topography, Using a protractor type compass, Prismatic compass use, using a sun compass, Finding north via a wristwatch,Astral navigation.
It's written as an instructional manual so is easy to follow has lots of diagrams and pull out maps of various types to practice on. I also has a section on interpreting aerial photographs. There is nothing in it as such on Night navigation and it misses out on techniques such as hand railing and aiming off but it pretty good.
I'd highly reccomend it to anyone.
cheers
John