Hi all, thanks for the replies.
And yes, maybe "scammed" is a better word ... you may have noticed I am no native [english] speaker

.
What happened is we agreed that I should sell him some hardware. He didn't pay, but then finally paid half of the money we agreed upon, promising to pay the rest later (in October).
I finally got tired of the excuses and transferred the money back and told him to send the hardware back. No answer.
Despite that the situation appears obvious, there are a few things why I do have reason to believe that this situation can be solved (without police and the like, that is

). It would take too long to explain the details here.
We shall see how things work out.
Thanks a lot again,
McTrinsic