The Tennessee Secretary of State maintains a database of all business entities that are registered with the state. This includes corporations and limited liability companies (LLCs). You can search for any business entity by name or by the state control number.
The entire database of registered business entities can be purchased for a substantial fee. It is available in tab delimited files that contain the mailing address, registered business names and registered agent details. Updates to the database can also be purchased for a small fee and are available in monthly or weekly batches.