My nikon d3000 is not comeing on, what can I do to fix it?

I recently bought a nikon d3000 on eBay and under the description it said it was in perfect condition. I think the battery is not keeping a charge. When I charge the battery and put it in the camera a little green light will come on in the bottom right corner. I'm not sure what that means can someone please help?

First lesson, never buy cameras, especially DSLR cameras off of ebay
you have no idea how they have been treated, what kind of abuse they have been through or anything else. It is very easy to lie about the product you are selling on ebay.
My suggestion, return it if you can, and get a new or refurbished D3000 from a reputable company like http://www.bhphotovideo.com/...video.com/ or http://www.adorama.com/...orama.com/ or even amazon.
never, ever, ever buy any camera stuff off of ebay.