There isn't one source that will cover every industry or have all of the information you could possibly need, so here are strategies to think about as you start your search.
Not sure where to start, try the Occupational Outlook Handbook (look for the most common industries under Work Environment).
Try a database that covers a lot of industries like IBISWorld or some of the others listed below
Search Trade Publications that focus on your industry. You can search Business Source Complete for a variety of trade publications.
Find a Trade Association that supports and promotes your industry. You might find (some free) career resources on their web page. Sources may include lists, and a quick search with Google will usually work.