Industry classification codes are a numerical method of assigning companies to a category based on their business activities.
In Canada, we primarily use NAICS (North American Industry Classification System). These codes can be used to quickly retrieve articles and data on similar industries and companies.
Important industry information can also be found from industry associations.
Use Google or another search engine to search for associations relevant for your industry in your location. If you don't find a something, try broadening your geographic area (e.g. from Ontario to Canada, or from Canada to the U.S. or international). If your industry is very specialized or new, look for associations for broader or similar industries. Try searching terms like industry association, industry group, trade group, or trade organization.
Don't forget to check the association website for additional industry stats. Many organizations make some of their research freely available.