Mine the company website.
For very small companies, one of the few places to find information is their own website. Some key locations to review:
"A list of people, companies, institutions, organizations, etc., in alphabetical or classified order, providing contact information (names, addresses, phone/fax numbers, etc.) and other pertinent details ...in brief format," - ODLIS
Use company directories to identify companies within industries, and to learn more about the companies such as locations, histories, and employees, officers, and directors.