Pick ONE book that has not yet been mentioned in this thread and why it is something an ambitious whippersnapper should read.
Anyway, for me, it would probably be Rich Dad Poor Dad. That was the first self-help book I ever read and it introduced me to the certainty/uncertainty and asset/liability paradigms. It's a very simple book, and can be used improperly(think real estate crash), but ultimately a good motivational work encouraging risk and audacity. It's controversial and some people hate it, which makes me like it all the more.
So first book in this library is rich dad poor dad.