Click here to change the background color:

Here is the large .png file with transparency. It's roughly 10mb.

Here are the layered photoshop files I used. I usually use Gimp to do my editing, so the .xcf file is what I used. It allows me to save as a photoshop file, too, so I included that as well, but sometimes Gimp doesn't save the layers all correctly in psd format.