1. Get the book texture. Get it here:
http://www.roblox.com/Item.aspx?ID=8566901 2. Save on your computer
3. Edit it with any image editing program.
4. Upload as a decal.
5. Open any place
6. Insert a book(Its OK if it still has a texture), a brick, and place your Decal on the Brick
7. Find the Decal in the Explorer and copy the link in Texture
8. Find the Mesh of the book. Erase whats in Texture ID and paste in the link from the Decal.
Your book should have your texture on it! Remember, the texture won't show on the site if it isnt approved.