I've often been asked,"I'm new to FOSS. How do I begin contributing? I don't know anything at the moment." I understand the situation that these noobs are in. After all, we've all been through it. In fact, I'm still in this position in a lot of scenarios. Well, really, the only thing to do is to dive in, keep your head down, and WORK.
Having said that, I spotted this email on the devel list a few minutes back: Announcing Easyfix. Easyfix looks really good, and it presents novice contributors plenty of opportunities to take up simpler tasks, and learn in the process. As always, to begin contributing, start with the join page on the wiki.