One of my favorite blogs is put out by Greg Lowe. I don't know Greg personally, but he always has good stuff.
One recent posting he provided was a full T-SQL script that will protect the Master database of a SQL Server 2005 server from unintentional schema changes. Greg puts forward the idea, and I agree, that 99% of the schema changes done to the Master database are done in error. His script can protect your server from this problem! Check out http://msmvps.com/greglow/.
Greg has also posted the slide decks for several good SQL Server 2005 sessioins including an "Introduction for Developers", "High Availability, Scalability, and Reliability", and "SQL Server 2005 Overview". Good stuff, Greg!
Let me know if this is useful for you.