You can find an amazing wealth of market data on the Internet, much of it free. The hard part becomes sorting through it and determining what information to use and what to discard. Your access to competitive information will vary, depending a lot on where you are and who the competition is. Competitors who are publicly traded may have a significant amount of information available, as regular financial reporting is a requirement of every serious stock market in the world. Wherever your target is listed for public trading, it has to report data each year.
Competitive information may be limited when your competitors are privately held. If possible, you may want to take on the task of playing the role of a potential customer and gain information from that perspective.
Industry associations, industry publications, media coverage, information from the financial community, and their own marketing materials and websites may be good resources to identify these factors and “rate” the performance of each competitor.