In case it does not work out, follow the $PJ$ steps:
1. File police reports with your local PD. Then contact his local PD and file said charges providing them with the police reports from your local PD. Try to speak to the same guy at his local PD. You will probably have to fill out a general affidavit.
2. File mail fraud charges. http://www.usps.com/postalinspectors...dComplaint.htm
3. File a IFCC complaint: http://www.ic3.gov/
4. Use www.411.com
to use the reverse lookup feature to find a phone number for him/her.
5. You can also contact your state attorney general and file with their cyber crime department, who will contact the local police departments and speed the process along.
Keep contacting the police on a regular basis.
Contact his parents if he is under 18