It may not sound as exciting as dashing around to interview franchisees, but plan to spend some time at the library. Explore marketing trends and business development statistics in your market. Find a book or two about franchising. Read up on preparing a good business plan. Even though you're considering buying a franchise, you can't assume any company will handle basic business planning for you.
Don't overlook the Internet. You'll no doubt find a Web site hosted by the franchisor and maybe some basic online information about the program it offers. Check out how the franchise system appears on the Net. Do individual franchisees have their own Web sites set up, or is the franchisor's trademark coordinated at one single site?
While you're on your computer, stop in at the Federal Trade Commission's Web site (www.ftc.gov). This site offers some interesting reading about enforcement actions against franchisors and general advice about franchise investing.