Obtaining Proof of no Crimininal Record from USA for Work Visa

I heard that the to obtain a work visa now you need to provide proof that you have no criminal record from your home country. How do US Citizens go about obtaining this? I have emailed the Guangzhou American Consulate and received the following response:

Thanks for your email. The Consulate does not provide any proof of no criminal record and you will need to contact the police department in your state of residence for the record. You may visit the State Department website http://travel.state.gov/travel/tips/emergencies/emergencies\_1201.html that has detailed information on how to obtain no criminal records.

In following this link there seems to be two options of getting the information from the local police department or from the FBI. I followed the link to the FBI Identification Record Request and here it says that you need to send in a request form with finger prints. Has anyone done this? What is the best way to do the fingerprints? Does the Chinese government accept what is sent back? I heard the proof of no record is supposed to be notarized and sealed which it does not sound like this is. Any advice would be appreciated.