Incompetech

For all your online graph paper needs. Incompetech.
http://www.incompetech.com/beta/plainGraphPaper/
Not only does this site instantly generate graph paper of several dozen types, it also makes kanji writing practice paper, English penmanship writing paper, dot, brick, trapezoid, polar graph, music notation staves, guitar & bass fretboard diagrams, and other types of lined paper of your specifications. Punch in the numbers and get a pdf immediately.
While there, be sure to check out the gallimaufry area of the Incompetech website, where Kevin expounds on Indeterminate Numbers, I Could Care Less, and other topics.