Free online dictionary and thesaurus. A great reference tool.
The Poynter Institute. From their mission statement: "The Poynter Institute is a school for journalists, future journalists, and teachers of journalists." Their Web site contains quite a bit of information by and about writers.
Writer's Market Guide. The premiere guide for writers seeking contact information and submission guidelines for magazines and book publishers.
Other Stuff:
The Huffington Post. The HuffPost features regular blog posts from Arianna Huffington and others who write about current events and politics.
justagypsy. My personal Web site.