The Site of the Week this week is the online version of the classic Web Style Guide. If you're new to the Web, this is the site for you. It will give you a broad overview of a very complicated subject and get you started in the right direction.
If you're battle-scarred, weary, and preparing mentally to do battle again, this is the site for you. It will help you synthesize and reshape your approach to Web site design from a more reasoned and realistic perspective.