making a book

I habe been publishing a newsletter and have been laying it up as a 14"x8.5" with back cover on the left and front cover on the right, so on and so on. How do a convert it to a book form so I can publish it as a e-book or pdf format. I want it set up as 8.5x7 so if people want to print it they can and it will come out formatted in the correct order. CAN ANYBODY HELP?