Industry (or trade) associations often provide detailed information about their industry, in the form of statistics, reports and news. While some content may be restricted to association members, it can still often be worthwhile to review the website of the relevant associations for the industry you are investigating.
You will often have success using a search engine like Google to search for "fill in the blank industry association." This directory is also useful:
Use the following databases to look for articles in the business press about an industry to gain insights into its major players, trends and performance. It may be appropriate to use fairly specific keywords: for example, "software" instead of the more general "computer industry."