I know theres a halo 3 thread but i thought this one can be dedicated to stats and linking your personal stats.(so we can find out how to get all the medals lol). and if you know any other hints like armour skulls.
http://www.bungie.net/stats/halo3/CareerStats.aspx?player=J1PpERs&social=false&map=0
http://www.bungie.net/stats/halo3/CareerStats.aspx?player=J1PpERs&social=false&map=0