Luke Duz Gaming

So I am making a mod/mapset for Doom 2 (GZdoom in Hexen format) and want to know how to make my character speak voicelines a la Duke Nukem/Shadow Warrior/Blood. I was able to make him "speak" with a script that displays text, but I want full audio. Can anyone explain how to do this? I also have basic knowledge of ZDoom ACS and WAD editing so anything can help.