Forget about printing--printing or reproducing a book by itself conveys no rights in or to it.If you were hired to design and otherwise create the book, then your design work would have been done as a work for hire. As a work for hire, the copyright to the book belongs to the customer, not you.Two caveats: first, if you were not paid for the design work--that is, if the customer should have paid you but breached the agreement and did not pay, then you would still have the copyright in the design and layout. (You would not have the copyright in the text if the customer provided that.) In that case, the customer cannot use your design, layout, etc., though he could have someone else design the book anew for him. Conversly, if he paid for the design, etc. work, it's now his.Second, if the agreement or contract with the customer provided that you were designing the book for him on the condition that you then print it, then he cannot take the book elsewhere--though again, if he provided the text, he can take his own text, but not any of your work, to someone else.