Some of the larger public libraries are subscribers to Reference USA, which lists millions of businesses by geographic region, sales, and within industries. Campaign Public Library (CPL) makes it available for in-house use, or if you are a card holder of CPL, you can access it from home using your library card number. ReferenceUSA also has some visualization tools for mapping.
The Zinio Digital Magazine collection offers trade and industry magazine in full text, including graphics. Among some of the notable ones in the collection are The Economist, Forbes, and Kiplinger Personal Finance. There are other "hobby"-type publications, which are useful for finding out more about brands and trends. Zinio is available at Champaign Public Library (CPL) for in-house use or they can be "checked out" from your computer, if you have a CPL account.