Depends how much you already know about photo. This is what I have in my collection:
Black and White, David Präkel
Advanced Digital Black & White Photography, John Beardsworth
Creative Black and White: Digital Photography Tips and Techniques, Harold Davis
Creative Black and White Photography: Advanced Camera and Darkroom Techniques, Bernhard Suess
Black and White Digital Photography Photo Workshop, Chris Bucher
I also have a bunch of B&W magazines... in PDF
... man, that's a lot of captcha verifications just to post on this forum!