So what I do is put an ambient_generic, point it to my mp3, play everywhere flag, and then I compile. Then I use pakrat to pack the sound file itself, which is located in portal 2/portal2/sound, then Resave the bsp. Still nothing.... At All. I spent all night trying to figure it out before I posted here, but I just can't get it.

You don't have to use pakrat, just distribute the files and let the people put the files in a custom portal2 file folder (portal2_dlc3)

I know thats an option, but why won't they work being packed into the bsp?

Possibly because there are requirements for the audio files, taken from the wiki:

wiki wrote:
Compatible specifications
Although you're not restricted to these, the following are known sample rates, bitrates, and channels that were used in official sounds:
.wav: 176, 353, 706 or 1411 kbps (doesn't have to be exact); 11, 22, or 44 kHz (must be exact); Stereo or Mono
Tip: Use 16 Bit PCM format, as this is common in most audio software and is supported.
.mp3: 64 or 128 kbps; 44 kHz; Stereo or Mono

hope that helped!

It's possible, but I got them working once, then they just quit working all together. I guess i'll fidget some more, and update you on what I find.

Do you have your map (the vmf file) in sdk_content\maps? and your sounds in the folder portal 2/portal2/sounds ?

Yes.. I do...

Do you compile with vvis on full? A fast compile once stopped it from working for me.