Sometimes a big challenge in freelance writing is finding sources (heck, even fiction writers can benefit--you might need some research). Well, Peter Shankman had a great idea...people kept asking him for sources, so he started a group on Facebook where writers and sources could find each other. It grew so big that it exceeded the 5,000 member limit on Facebook and he had to start his own site, Help A Reporter Out.
The process is simple. If you're a writer and need a source, you fill out an online form. Your request goes out in one of two group emails each day, and chances are, there is someone in the thousands of people on the list who can serve as a source for you.
If you are interested in giving back and being a source yourself (of course, you must agree to only answer questions you are truly qualified to answer), you can sign up and you will start receiving three emails per day. You may get the chance to be quoted in an article and help someone else out--and you might find some inspiration in what other people are writing about (not that you should copy them, but something might inspire you).
Give it a try!