A Book is also available at your local Barnes and Noble, or Amazon.com. It is called "The Complete Price Guide to Watches", by Cooksley Shugart, Tom Engle, and Richard Gilbert. It is very popular book among collectors and will help you determine an estimate of what your watch is worth. Again, the true "value" of a watch is what someone is willing to pay you for it. Books can only give an idea of the value.