I found this great pad at a local art supplies store. It's perfect for those of us who like to create tangle patterns on a grid.
It's narrow (2.9 by 8.3 inches), and the cardboard backing is very stiff. The cover is pre-creased so that you can fold it over the top of the pad.
The pages are perforated to make it easy to tear them off.
It comes in other sizes too. The only place I have found them online is amazon.com (search for Alvin Saray Note Pad).