Okay, not sure this is the right place to ask that but I don’t know where to :-[

Two weeks ago I bought the Sleipnir Zombieheadshot was selling here: http://yoyoexpert.com/forums/index.php/topic,29058.0.html
But he has never been active since I sent him the money, nor replied to the e-mails I sent him…

I would feel really bad to say he is a scammer if he is not…
Has anyone ever dealt with him?
Does anybody know him personnally?

Any new member who doesn’t want to ship first should not be dealt with. Whether or not they bring up the issue of not trusting anyone anymore. But there is a chance that he just legitimately hasn’t been on, and is not trying to avoid you.

Depending on how you sent your payment, this can be easily resolved. If you sent it via Paypal, just file a claim.
If you sent it over the mail, you have a perfect case for Federal Mail Fraud. Which is quite easily filed, and usually comes out the right way, if you kept all of the PMs between you and Headshot