Notification image

Not sure if this needs to be posted in the Night section but I figured this is in all skin's. Also not sure if this image is different in other skins as well.

I currently have sickbeard and couchpotato sending notifications to my primary xbmc machine telling me when a tvshow/movie is snatched and then another notification telling me that the media is completed downloading.
The notification popup is center bottom screen. It is awful looking. Its a plain white box with rounded corners and a light blue circle with a red exclamation point.

Can someone please tell me how to extract this image so I can replace it with something better. I am going to keep the same shape, get rid of the ugly image, maybe add a gradient or something. It would be nice if this would pop up in the bottom corner with a nice animation or something.