http://www.bipolar.com/
This site has a good amount of information about Bipolar Disorder.
http://www.bipolarconnect.com/
This is a great site to connect with others going through the very same things you are.
http://www.mood247.com/
A fantastic tool that can be shared with your healthcare providers and charts your mood on a daily basis through text messaging to your phone. You simply reply with "mood X" and the X is a number from 1-10 to dictate how your mood cycles are going. I have been using it for about 3 months and my doctors LOVE it!