I just finished up a case of identity theft...the perpertrator is
Washington Correctional Facility for Women after conviction.
Here's what I did:
Contacted the police where the id theft occured. You will have to make
a formal written complaint. That gets you a police report with a number
issued and an investigating officer's name and contact number. Provide
them with all infomation regarding any fraudlent charges on credit
cards, any new accounts opened, etc.
I contacted all the financial institutions I deal with and forwarded
them a copy of the police report and filled out all pertinent forms
since a fraudulent bank account was opened in my name and the perp had
bounced $10,000 in checks.
I contacted all credit bureaus and immediately put an ID theft
notification on my credit rating. They also were sent a copy of the
report.
I contacted all credit card companies....and discovered that there were
unauthorized charges on some accounts. Upon receipt of the police
report, they deleted all charges and notified the credit agencies.
Since your SSN was fraudulently used, you need to contact the Soc. Sec.
Administration...and send them a copy of the police report also.
When you get a copy of your credit reports, it has the adresses you
have lived at on the reports. Inform the police if any of those
addresses are not yours. The perp may have slipped up (as in my case)
and used his or her real address!

Keep copies all correspondence. You often will need to send copies of
materials you recieve from other agencies and companies to the credit
bureau, police agencies, SSA, etc.

Hope this helps.

Sandi