Scourge of War Boards

The Seven Years War Wikipedia:

http://en.wikipedia.org/wiki/Seven_Years'_War

On the Art of War by Frederick the Great

This edition of Frederick the Great's military instructions to his generals (edited and translated by historian Jay Luvaas) is no longer in print
but you can pick it up cheap on Amazon.com.

Or you can check out Frederick the Great's military instructions to his generals on-line:

http://www.sonshi.com/frederickthegreat.html