"Narcissists Suck" has been for me one of the best resources on the web for understanding NPD. I highly recommend it to anyone seeking answers to their dilemna of having a person with NPD in their lives. Although "Anna", the brilliant writer of the blog doesn't post often anymore, the content that is found there is a goldmine of pertinent information just waiting to be discovered. Her insight is profound and her ability to convey her thoughts in writing is, in my opinion, unmatched.
If you haven't discovered her blog yet, here is the link- http://www.narcissists-suck.blogspot.com/ . I would suggest starting from the first posts and moving on from there if you have the time. If not, you can choose particular subjects to navigate through. I've been a follower since the first day I discovered what malignant narcissism meant and her writings have helped me immensely. I only wish I were so eloquent!