Information on private companies can be sparse.  Private companies are not required to file any financial data in the U.S., with the exception of registration data filed with the Secretary of State, in the state where they are registered.  Databases like Nexis Uni which replaced Lexis Nexis Academic have some basic data on private companies. Often 'local press' have more stories on a locally based company than national newspapers. (e.g. Spokesman Review versus The New York Times).  Local newspapers can be found in the News part of  Nexis Uni and in US Newsstream.