To be honest, I never thought about the necessity to print blank sheets of graph papers. But in case you ever need such a thing, here's the right application for you.
Graph Paper Printer is a simply designed, easy-to-use tool with which you can print a wide variety of graph papers – obviously blank ones - that you later on can fill in with anything you want. The program features many different types of graph designs, from Cartesian paper to hexagon, triangle or brick patterns, including also tables and music manuscripts.
You only need to choose the kind of graph you want to print and adjust it to the size of your paper. Most of the graphs have a few configuration options relating to line width or space between lines, but you won't be able to add your own values – just choose among the ones Graph Paper Printer offers.
If you need any kind of graph paper, use Graph Paper Printer instead of running to the mall and you'll get it at home in a very easy way.