Antonio Centeri, a 44-year-old Westhampton Beach special education teacher, was arrested on charges he arranged to have sex with who he thought was a 13 year old girl he had met in an America Online chat room.  Instead of talking to a teen, Centeri was actually talking to Suffolk Det. Rory Forrestal of the Computer Crime Section.  He allegedly arranged to meet the supposed teen at a Pathmark parking lot off the Montauk Highway in Shirley for the purpose of having sex and was arrested after police placed a young girl as a decoy at the scene.  He was charged with second-degree attempted rape, second-degree attempted sodomy, disseminating indecent material to a minor in the first degree and attempting to endanger the welfare of a minor.  He is being held at Suffolk County jail in Riverhead after he failed to make $20,000 bail.