Picked up from Much Ado Books, a great second hand bookshop in Alfriston. Not quite sure how to rate this one, as most of it is largely a (fairly dry) summary of a lot of complex maths and tables that go into the more advanced divination in Chinese culture. That said, it's an interesting overview of the area beyond basic I Ching usage, and could serve as a good intro to someone interested in taking things to the next (next) level. I couldn't say if there are better, more modern guides in English these days, although I guess you could find tables and charts that cover the current year.