What is the salary of an Ambassador in the US?

Answer 1

If you are asking what is the salary of all the various ambassadors of other countries who are working in the US, that depends on their own governments' pay scales. It can range from pretty generous down to starvation.

If you are asking what is the salary of American ambassadors to other countries, that is governed by the Foreign Service Pay Scale. Here is the latest:
http://www.afsa.org/2006pay.cfm

Ambassadors are usually members of the Senior Foreign Service, which covers a few grades above the Class 1, at equally increasing rates of pay.