|Contact YouTube with proof of copyright and they will take the content down.|
As for tracking him down, you'd need to take legal action, forcing YouTube to disclose the IP address from which the content was uploaded.
Then you'd need to do the same to get his ISP to disclose their customers details (most are unlikely to do so without a court order).
Then you'd have to take legal action against the offender and the chances are he'll get a slap on the wrist.
Starting to sound like an expensive exercise, isn't it?
My advice.....just settle for having the content taken down.
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