Help: How to add voices for in game units

I need help in adding voices or replace them in game (WC3 of course). and i want to know what are the extensions for the wc3 sound files and what program to convert them to it. in other words. I need help really badly.

i'm using sound forge as my default music editing thing.

wav is detected as sound.
For unit responses I would use wav, since it is faster then mp3, and it will actually make that much of a difference. For responses go for the 22.5khz 16 bit mono.
For normal voice lines go for the 128kbit mp3 encoding.

As for replacing, just look up the paths to the responses and rename your path to that. Then the map will use the ones in the map instead of the ones in the mpq.

Example: MuradinPissed1.wav Will have a path like this: Units\Human\Muradin\MuradinPissed1.wav

so the in the game theres every file for every sound? right? not like a play list.