"Competition: Alternative firms that could provide a product to satisy a specific market's needs." - Kerin, R., Edwards, G., Tibbo, G. (2005). Marketing: The core. McGraw-Hill Ryerson; Toronto. (p. 65).
Various media and organizations will list and rank companies according to certain topics, metrics, and surveys.
Annual reports from incorporated (public) companies are distributed to shareholders and, generally speaking, are required by regulations. Typically annual reports include audited finanical statements and information on the company's performance.
TIP: Look for the MD&A (Management Discussion & Analysis) in annual reports. MD&As will provide "information to the reader that management believes is useful in understanding the company’s operating results, cash flows, and financial condition" (Full Disclosure Background, 2006).
Use directories to identify companies within industries, and to learn more about the companies such as locations, histories, and employees, officers, and directors.