From what you've said, I'm not sure his parents are going to be able to do much. If it's true about his father, then they might not be able to pick him up anytime soon. I'd give them a call anwyays. But if nothing comes of it... And you don't want to get either the police or your landlord involved, why not just buy him a bus ticket, tell him you're bringing him there, to grab all his stuff, and then take him and drop him off. Then try to get the locks changed immediately if you think he'd try to worm his way back in.

I agree that you should investigate some free legal advice (I've seen them have offices in the court house before, you could try there) and consider turning off electricity and hot water (if anything, simply cause you aren't using it!).

Good luck, keep us posted!

Ro