My friends and I are just about to start playing D&D but we're all new. The DM is also new though, so he doesn't know the answer to my questions. My race/class is Elderin/War Wizard if it helps. 


What is a spell book for? 

How do I learn new spells? (I have the feat Enhanced Spell Book) I read something about wizard levels - is this different from normal levels?

What is a ritual book for? How can I do rituals?

How do you check spell damage?

My armor proficiency is cloth - does that mean I can only use cloth armor or just that I have a proficiency for it?

Is there anything else I should know - particularly for my race/class as I'm the only wizard?