a
instead of game-protocol you should go parse replays.
start by checking these;
http://code.google.com/p/starcraft2replay/ (http://code.google.com/p/starcraft2replay/)
http://code.google.com/p/phpsc2replay/ (http://code.google.com/p/phpsc2replay/)
http://code.google.com/p/sc2gears/ (http://code.google.com/p/sc2gears/)
Than you have a lot to figure out. First you've to authenticate with bnet2.0 service and reverse engineer your way to packets related with match histories. good luck.
There are many people out here (especially on irc) that knows how to authenticate with bnet2.0. just ask for it on irc then.
you can get the answer on irc.