Hay! Awesome! At least I know who made this now. I have had that image on file for a long time, and have even used it as my avatar. I honestly found it on Google labeled under Pinkamena and Butchershy. I don't know if you knew that it was labeled that way else where, or that someone else may have put it on there that way, but I've always liked this image.
There was an MLP instrumental on YouTube somewhere with this as the cover image, but I can't remember what it was called. I think it had "Equestria" in it (because that definitely narrows it down). Does anyone know what it is?