SQL Server articles and references
MSDN is starting to publish 2 articles per month from SQL Server magazine. There's no link, but the articles appear in the MSDN Just Published RSS feed. I've had a subscription up until now (when my free year for getting my MCDBA ran out) and it is a good magazine if you are in SQL Server all day. Not to knock it since I work with SQL Server a lot, but not enough to warrant spending the money on the magazine.
SQL Server Books Online (you'll often see it abbreviated BOL), updated for SP3, is one of the best references you can get and covers 95% of what you need to do. Book-wise, Admin911: SQL Server 2000 is great for admin topics (I used it to study for exam 228) and to really get into the details there is the preeminent Inside Microsoft SQL Server 2000 by Kalen Delaney.