[drunkn]

Front View

Back View

I can't seem to find a diagram online for this type of jack.

The headphone cable has a green, red and black wire.

 

[fameh]

That type of jack is a 1/8" TRS, which is the most common in portable mp3 players, for example.

Maybe this can help you:
TRS connector - Wikipedia, the free encyclopedia

There are the 2 stereo channels and another one for the ground.
Don't know where are you located, but i would say the ground/earth cable color is the green.

 

[Billyk]

I think what you are looking for is here. This looks like the one you are showing. Not the simplest jack to solder that's for sure. I would highly recommend some flux from a flux pen or similar to make it easier to make the joints.
If that's not quite it and you need basics, the tip is left, the ring is right, and the sleeve is ground.