A programming book from developmentor [http://www.develop.com/] (Don Box, et al.), this book gets down and dirty on windows security programming. While a bit dated now (Windows 2000), many of the concepts and technologies are still current.
Great explanation of windows security fundamentals. It's certainly dated but gives you a great understanding of where things started. I really wish I had read this back in 2000 when I was still fighting Windows Auth issues.