D300 Tutorials / Reading Material

I have a D300 and I really would like to have a better grasp of this camera, the various settings and features, and where and when to use which settings.

Can anybody here recommend a book, a website, or another resource to help familiarize me? I'm coming at this from a novice perspective. I'm not a complete dunce, but it has been quite some time since I've spent any extensive time behind the lense.