Can't believe this hasn't been locked yet, well actually it really does all depend on what you mean by the term 'hacking', do you want to learn how to take apart your system and secure it?

Well anyways... if you want to learn Assembly, the book AoA (Art of Assembly) is really the way to go, if you want to learn win32asm (programming windows applications in asm (assembly)), then check out hxxp:///win32assembly.online.fr/
The AoA can been found at (I recommend the 16bit version and not the 32bit version due to HLA):
hxxp://webster.cs.ucr.edu/