could try this:
http://uk.gamespot.com/pages/gamespa...=6094495&mode=
Or
http://www.fileplanet.com/filelist.aspx?s=98034&v=0
But as far as I know bungie the makers of halo didn't release an SDK(software development kit) so the community had to make their own such as above.
although for gamespot you need to register not sure if its free or not give it a try. They also had another tool search halo on their site.