http://www.blockcentral.com/quiltblocks.shtml
This is a link to some quilt block ideas to get you started. If possible, I think it would be nice to have the blocks made by many different people and then assembled. To keep the quilt consistent, you might have to specify or even provide the background fabric. Because this pattern adds the shelves later as sashing, you'd have total control over that. Since it it paper pieced, many skill levels should be able to return a usable block to you. Maybe ask the makers to included at least one favorite book name on the spines.