License plate numbers can not be tracked by individuals; this requires someone of authority to contact the state's department of motor vehicles, or DMV, to release the ownership information. The DMV will only release the information to licensed professionals.
The DMV can not give personal information out to the public. There are many malicious websites and companies that offer services that use old out-of-date information regarding the owner of the license plate number. This confusion costs consumers money and does not provide the intended services.
The DMV can, however, release the information to licensed professionals, such as private investigators, lawyers or law enforcement. Using a licensed professional is the only legal way to track the plate.