This would be useful if they weren't so expensive! Guess I'll have to stick with contact paper.

Expensive? When paperbacks are $20 these days, a $4 cover that makes them into a hardback is practically free, when you consider that it increases the lifetime of that book to the point where by the time you wear it down after decades of reading and transporting (if it wears down at all) you won't have even missed the $4.