FYI, in some states, a private person CAN go before a magistrate and "swear out" an arrest warrant. I am not sure if the OP's state is one of those.
EDIT: From his reply above, I think it is.
If the court is notified of a violation of probation, through whatever means might be appropriate, the court can issue a warrant for the arrest of the suspect. I HAVE seen warrants issued from Family Court in my state when the court was advised of violations. I was present in one case where the judge actually told me to go find the defendant (at her home) and arrest her! How it might work in the OP's state, I can't say.

