Given I actually read newspapers and things of that nature, many times salaries are listed.
At the top tier Divison I programs the head coaches make 80-110K. There are some excpetions higher (LSU, Arkansas, etc.). The Big 10 coaches I know fall into the above category.
In the middle of Division I the coaches will make 45-65K
At the bottom of Divison I the head coaches will make 25-45K
Assistant coaches are all over the map. I know Division I assistants who make 20K, while I know others who make 40K. This is for the middle group.
A friend of mine went from being an assistant coach at a middle tier Division I program making about 40K to a head job at the Division III level, making 33K.
One of the top Division III colleges in the country asked me to interview for their head coach job. The pay was about 35K.
Peace