I'm not sure if I should post under Science fiction on under illustration. I'm an author illustrator (and publisher) . I write science fiction books and also do the book design and illustrations. My card modeling experience comes in handy. A paperback book is basically a card model, same paper, same glue. I'm pretty sure the stuff on the spine is PVA. Here's the cover flat for my second book, and also a proof of the book on my workbench with cardmodeling tools. I designed this using Coreldraw, Autodesk Sketchbook Pro, PhotoShop, and inDesign. I've found I can mockup books by using cardmodel techniques. I print the cover out on two sheets of photo paper then cut, glue, and score. I've been unable to find photo paper in legal size so I print on letter size then cut and glue. I attach the cover to an appropriately sized book using poster putty. It takes me about a year to do a cover illustration, but I'm also writing, editing, attending cons, marketing, and doing interior book design.