The site that I found is www.blanksheetmusic.net.  There, you can customize your staves to fit your needs.  First, you start with a blank sheet and go from there.  There are options to add more staves and connect them for piano or ensemble pieces and to add add tab to your project.  One feature that I liked, in particular, was the ability to adjust the size of my staves.  In my case, I needed to enlarge it to make it easier for her to write her piece.  Once you are finished with the customization, they give you the option to save it for future use (requires registration).  If you don’t need/want to customize, they have pre-configured staff paper available for you to use as well.  It’s as easy as customize and print.  I great resource for any songwriter.