http://www.issf-shooting.org/
This is the governing body for international competitions such as Olympics and World cups. There are lots of pdf’s of rules for different sorts of competitions. For a brief article with an overview of the areas available including photos of shooters in the latest gear look here:
http://www.cbc.ca/olympics/shooting/story/2008/05/09/f-olympics-shooting-essentials.html
Some of the gear they have to wear looks funny.