Skully - I know you are upset right now and it appears as if you definitely are due the 2 weeks pay. I unfortunately do not know who you would report the company to, but I believe some good leads have been given above.

Regarding your friendship; I would try not involve your friend in this matter at all. It's not her you have the gripe with, and in a way you are putting her in the middle.
If you want this relationship to survive, deal with the company directly.
I know this sounds harsh, but I'm just giving my opinion.