The USFWS collects a lot of data from the states and from surveys. One of the things they attempt to do, is place a dollar amount on hunting and fishing. They issue these reports every 5 years.

Here are some links:

2001 National Survey of Fishing, Hunting and Wildlife-Associated Recreation State overview
http://library.fws.gov/Pubs/State_overview01.pdf

PRELIMINARY STATE DATA FROM 2006 NATIONAL SURVEY OF FISHING, HUNTING AND WILDLIFE-ASSOCIATED RECREATION SURVEY AVAILABLE
http://www.fws.gov/mountain-prairie/pressrel/WO27.htm

2006 National Survey of Fishing, Hunting and Wildlife-Associated Recreation State overview
http://library.fws.gov/nat_survey2006_state.pdf

These reports are your tax dollars at work.

Pete