#0 - The Theory of Money and Credit by Ludwig von Mises
http://www.mises.org/books/Theory_Mo.../Contents.aspx
This is sort of like the Theory of Poker except for life instead of poker.
#1
The Quotable Mises. Exactly what it sounds like.
http://www.mises.org/books/quotablemises.pdf
#2 - Freedom Under Seige by Ron Paul
http://www.mises.org/books/freedomsiege.pdf
#3 - Gold, Peace and Prosperity by Ron Paul
http://www.mises.org/books/goldpeace.pdf
#4 - As We Go Marching by John Flynn
http://www.mises.org/books/aswegomarching.pdf