Wookieepedia - The Star Wars encyclopedia that anyone can edit.
If you have a billion hours on your hands or just have a quick question that none of your sci-fi buff friends can't answer then Wookieepedia, the Star Wars encyclopedia that anyone can edit. If you are an uberfan, you can jump on and make a few entries yourself.
I wish they would have had this up back in my Star Wars the Role Playing Game days. It would have helped a GM out. I should go on and add my old character, Reignchilde. She was always working behind the scenes making sure the Empire was heading for a fall.