Does anyone out there know anyone?

I’m having problems with YouTube.
As it turns out – there are some people out there who are taking music from my site, claiming it as their own, and registering it with rights organizations (of some sort).
The music-matching engines on YouTube are now flagging my content as theirs. Can I contact these people and tell them to stop? Not really – when the messages get sent to users, they do not include contact information.
Has this happened to you? Please send me as much information as you can on the entities that have claimed ownership of my music.
It may help me track down the jerks who are pulling this on the “owners’ rights” side of things.
To stop this from happening to you; credit, credit, credit. Include the name of the piece you used (in the text description – so it is easy for YouTube employees to find). Include my name, my site, the license used, and the ISRC number of the recording.
Hopefully, this strategy will work for you.
And if you know of someone in the YouTube rights department – please ask them how I can get this to stop. Can I register my music as a preemptive strike? What can I do here?
Update 1: UMPG Publishing is claiming at least one of my pieces… not sure which yet.
update 2: I have applied for the YouTube Content Identification Application.