Incompetech has an amazing array of customizable graph paper for just about anything you can imagine.  I was particularly impressed with the storyboard, accounting ledger, and perspective drawing graph paper.  But don’t let me spoil all of the fun — check it out for yourself and find a graph paper that best suits your needs!  By the way, Incompetech also has some other interesting content, such as a nifty and simple mailing label generator and free theatre scripts.