First, we've finally got the TF2 Community Submitted Avatar Gallery up, containing the thousands of avatars that you fine folks have submitted to the TF2 Contribute page. If you find a submission you like, all you need to do is click on the link below it to switch your steam avatar over to it. There's a ridiculous number of great avatars in there, so we're sure you'll find something to your liking.
Second, we love eXTV's latest video, an Intro to Competitive TF2. It's an awesome primer on competitive TF2's terminology, class usage, and common strategies.