The Indianpolis Star's David Woods has written nearly 2,500 words on the money side of the sport.
A highly recommended read.
http://www.indystar.com/story/sports/2014/06/23/pro-track-athletes-make-little/11282551/
It includes some great nuggest of info like how much Morgan Uceny made after college.
For many, the money is irrelevant as the dream of an Olympic bid is enough. That's not true for Andrew Poore, who retired after finishing 4th at USAs last year because he made just $5,000 on the year.
The article also has some good quotes from USATF head Max Siegel who says he finds the animosity towards some of the shoe companies to be strange given the fact that in Nascar the support of the motor companies is positively viewed by the fans.