Consider them as a potential interviewee and ask for names of people they could refer you to. Newspapers offer a variety of possible leads. Look at the classified listings for organizations and names of people in areas that interest you. Wait a month after the listing appears before trying to set up an informational interview. This way you can gain insight into who they hired and why.
Newspapers also cover local and national business activity.
Each event reported gives you a reason to call that particular business and demonstrate your knowledge and active interest in the business community. Check out the Telephone Yellow Pages. Use the index to search for headings of obvious interest and browse other sections to find connections to your interests. Professional associations can provide possible informational interview contacts along with trade papers and newsletters. To find these organizations look up your field of interest in the Encyclopedia of Associations in the Career Library.