HelpAReporter.com is a free service offered by Peter Shankman. You sign up as a Provider of information and/or a Seeker of information. Three times a day, Peter sends out an email to the providers containing queries from the seekers. IF you feel qualified to comment you merely reply directly to the Seeker's email included in the query listing.
Reprinted from "The Book Marketing Expert newsletter," a free ezine offering book promotion and publicity tips and techniques. http://www.amarketingexpert.com