http://www.helpareporter.com/
I was recommended this site on a book writing forum as a suggestion for building a platform. At "Help a Reporter Out" you can join as either a source or a reporter and search for either according to your needs. If you're a reporter for anything from a school paper to large publication you can find sources for nearly any topic. The catch is that these "sources" are people like you or me. Essentially self-labeled experts.
That's one possibility. The other is more why I posted this here. If any of you have ever wanted quick, free media access to get your name out there, this could give you a real shot. I'm not saying as soon as you sign up you'll be quoted in the New York Times, but there are plenty of instances of HARO being used for large outlets.
I haven't signed up myself, as I really have nothing to offer. But, I'm sure the rest of you are just an ocean of information. I'm interested to know what each person would cite as their area of expertise.
I'm tempted to try "women" just to see if it gives an error.