Are war ration books worth any money?

Yes, of course. Often wartime ephemera, such as less common pamphlets and so on, are of some value as most copies seem to have been thrown away. (Obviously, things are literally everyone had, such as ration books, are usually of no great value). Original copies of some books dealing with matters that were relevant at the time may be of value, for example, a copy of Guilty Men by "Cato", published by Victor Gollancz in July 1940. It has been reprinted, but copies of the reprint are not cheap. If you have books and pamphlets from World War 2, keep them and get advice, but don't be disappointed if they don't turn out to be very valuable.