I won a giveaway but the guy won't show up

Track him down and kill him. That's the only thing you can do about it,there's no answers in the FAQ at all,where questions like this are suppose to be answered.

if he hasm't delivered on the seventh day, hit not received

If he doesn't deliver a game after 7 days mark as not received and move on.

You better kill the hater:
http://www.youtube.com/watch?v=jK2HepAqfJ0

Maybe he doesn't like you.

He has until the end of the day to give the game to you. I suggest that you double-check that your email address on SG is correct (just in case) then wait until the 7 days are up. At that point you probably won't be getting the game, so mark it as "not received".

It's generally a good idea not to contact the creator of the giveaway before the 7 days are up unless he asked that you contact him - people are different and some dislike being approached by the winners, and a handful even wait until the last moment to give a game if they feel that they're being harassed. That might seem like an odd reaction, but the giver is entitled to wait up to a week for whatever reason so just be patient. And if the giver doesn't give the game after that time - it's a pity, but life goes on.

kidnap him and keep him imprisoned for 15 years. Then hypnotize him to knock up his own daughter, let him beg to be your bitch, and then kill yourself for fulfilling your quest of vengeance. Finally, watch a cheap Hollywood knock-off of your diabolical plan from Heaven/ Hell/ Valhalla/ Xibalba or whatever you believe in.

Or you can just mark not received.

I've got the opposite problem. Somebody won one of my giveaways.. yet wont claim his prize.

Maybe he just died.

Just wait for another day and mark it as "Not received" and carry on.

After a week mark as not received and let it go.
I'm still trying to understand these topics, why people ask like this "Is there something I can do?" it looks like "So, is there any way to be compensated for the free game I didn't receive?"
I'm not talking to you personally but to everyone that do this same question.