The number of establishments in each industry, broken down by size, may be found in County Business Patterns. Reports are organized by NAICS, the North American Industry Classification System. [https://www.census.gov/programs-surveys/cbp.html]
For small businesses run by the self-employed, refer to the Nonemployer Statistics for states, metro areas, and counties. [https://www.census.gov/programs-surveys/nonemployer-statistics.html]
The ReferenceUSA database at JerseyClicks includes a directory of more than 14 million U.S. businesses. Click on the database link and enter your local public library card number. Use ReferenceUSA to find basic information about one company, or to find companies in an industry or in a particular city. It will also provide information on employees, sales, product lines, parent/affiliate/subsidiary companies, and key personnel. [http://www.jerseyclicks.org]
You can consult these videos to discover sample search strategies and learn more about the features of ReferenceUSA.
These two directories focus on specific industries or products:
More generally, these two directories allow searching by geography and by yellow pages business categories:
You can also search by selected occupations for licensed practitioners in New Jersey:
Chambers of Commerce: