What if I break or lose my iPad?!

I lost my iPad at school. Is there a way to track it?
My iPad was stolen, how do I get a new one?
I think my family purchased AppleCare+ for my iPad. How do I check?
My iPad is broken and I have AppleCare+. What do I do to get it fixed?
My iPad is broken, and my family did not purchase AppleCare+. What do I do to get it fixed?