I think that the Adams' books mentioned above are good darkroom references. But for pure printing (and developing and exposing) information, I would recommend Lambrecht's "Way Beyond Monochrome" and McLean's "Creative Black and White Photography" ahead of the Adams books.
Unfortunately, 'Way Beyond Monochrome' is sold out and won't be reprinted until Edition2 in Spring 2010. However, in the meantime, I recommend the three Ansel Adams' books. No serious printer should be without them.