Who are your customers? For basic demographics (people, income, ages, home ownership, etc.), start with these:
The database Reference Solutions (formerly Reference USA) is useful for searching for area businesses by county or zip code, to develop a list of competitors or a mailing list, for instance. It is available through many public libraries, such as those in our Southern Adirondack Library System. Search it online by logging in with your library card number.
If you're researching a company's organizational strategy and need information about the company, use these research guides: