game-editor.com

I think GE should have an in-built sprite creator or editor.

It's understandable why you'd think that to be necessary but most game dev tools don't have built-image editors and to try and put one in gameEditor would be stretching valuable time away from more important development. As it is I think we'll be very lucky if we recieve one more version.
If you are looking for a good image Editor I might suggest paint.net (if you don't use Windows try Pinta), if you want something more specifically suited to sprites there's asprite though I don't use it myself.

You've got a point there, Thanks.