The easiest way to get a different Language
1. Go to your installation folder of StarCraft2 and create a random textfile in the versions folder.
2. Name the textfile according to the Language you like
enUS (English - US)
enGB (English - GB)
frFR (French)
deDE (German)
esES (Spanish - Spain)
esMX (Spanish - Mexico)
ruRU (Russian)
koKR (Korean)
zhCN (Chinese)
zhTW (Taiwanese)
plPL (Polish)
itIT (Italian)
ptBR (Portuguese)
you can put as many as you like in the name of the textfile.
3. Then run the Repair.exe
4. Wait Repair.exe will download the needed files. The files for one language are around 1 GB. (After patches Repair.exe is needed to download the latest version keep in mind that korean versions may get patched a day or so later)
5. go to the Variables.txt (On Windows7 /Documents/StarCraftII/
6. change localeidassets to what you like (i.e. localeidassets=koKR)