Health Insurance explained (Krankenversicherung)

No, I am not going to explain how the health insurance system in Germany works. Why? Because, I am looking for tips as to where this is explained in a manner that is digestable.

I went to a few larger book stores recently, trying to find something to read on the subject. Obviously, I expected something like "Krankenversicherung für Dummies". But, fuggedaboudit.

I know that there is a difference between private insurance and public (Krankenkasse). With private insurance, doctors like to see you and with public insurance you can sometimes end up waiting quite a while.

Theoretically, everyone is insured in Germany. But, you still have to pay. I think. So, if you don't pay, do you lose your insurance? Even the public type?

I also believe that people above a certain income level are not eligible for public insurance. And, if you go to private insurance, then you have to stay with private insurance. You can never return. Is this like Hotel California?