Look into citizen journalism sites like Examiner.com
(I think that's the name). However, it may take you some time to get approved at Examiner (like a day or two). Can your story wait that long? Examiner gets a lot of exposure, but if you're in a hurry, try one of the others. These will mostly only pay you by pageviews, but if it is really as huge as you say, you're page view revenues may exceed what you'd be paid for the story upfront.
Other CJ sites include:AllVoicesAssociated Content
(offers upfront pay AND revenue sharing...may be a good choice)GlobalReporter.com
You may also try to sell your article on Constant-Content
. My only concern is that it will take you several days to get approved as an author and then the article will have to undergo a review for several more days. However, the pay can be really good if it's sold there (you get to name your price).
My brain is a little tired now, but if I think of anything else, I'll let you know.
Ah, just thought of another one: The Huffington Post
may be interested. They do a mixture of CJ and pro reporting...it's worth a try!
Each time I hit send, I think of something else, lol. Instead of trying to get the news outlets to buy a story from an unknown/unproven journalist, try contacting some established journalists directly and seeing if they want to partner with you on the story. Of course, you'll be giving away a lot of the credit, BUT this may be a good way for you to break in and reporters are often more receptive to breaking news. You might want to try some of your locals first and also look a few up on Twitter to see if they're interested.