I sent in a request through email because my access code expired before I could access the website and a USCIS representative called me and gave me a new access code over the phone. Try to email a request and hopefully you get a response, they contacted me a few days later.
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Date Application Sent -8/18/12
The Lockbox the application was sent to - Dallas Lockbox/Nebraska
Mailing Method (Express, priority, certified) etc. - USPS Express Date delivered - 8/20/12 Biometrics-9/17/12 Approved I-765: 10/31/12 Yay! I821-D Approved 11/1/12