http://www.freewebz.com/yobguls/War3BetaCrack.zip

1) Download it.
2) Install war3.
3) Download patch 1.03 here
4) Apply 1.03 (don't get it from battle.net)
5) Run War3BetaCrack.exe
6) Log onto battle.net and choose custom game.

Any problems, post them.