I need some help please?

i am a student in computer networking and systems technology at my college. i have a server 2008 cl. server technology is something i have never experienced so its kind of hard for me to grasp some of the active directory concepts. is there a place i can go and get some easy basic knowlege? this book expects me to know what the hell it is talking about and i dont.. i know server 08 is pretty much obsolete right now because of R2 but still i gotta p this cl.