Go to this post in the screenshots forum. Note:- TS2009 stores screenshots in JPG format which is what is required, earlier versions store screenshots in TGA format and they have to be converted to JPGs to host them.
I use Photobucket & Tinypics, I would reccommend the latter of the two at the moment, because there have been posts on another forum complaining of malware on Photobucket, don't know if they have sorted it yet.