This is some graph paper I designed to help with drawing four-point perspective. Four point is the one where lots of lines are curved and it warps the picture so you can see (for example) an entire room at once. This grid is specially adapted for drawing the interior of just such a room with the addition of bold outlines for the walls and extra vertical lines across the "surface" of said walls. The walls are twenty grids wide and ten grids tall, making for a medium/large room if you assume the lines are one foot apart (20x20 foot floor space with 10 foot high cieling...). Obviously you can see one full wall and two half walls per page, so it would take two pages to draw an entire room.
This image is the same size as american letter paper in landscape (11 inches by 8.5 inches) at 600dpi and is suitable for printing. If you want to print it, make sure you download the full size AND tell your software to print without scaling (maybe tell it to "Crop" or "Preserve Dimensions").
If you're not sure how to use this grid, try looking around online a little bit; there are a few tutorials around. Here's a quick one I found on deviantart
which isn't very detailed, but does a great job of demonstrating the general idea. I'll probably post some of what I'm drawing on these grids tonight/tomorrow/soonish, so that might also help.