Photoshop file for a wallpaper I made a little while back. Just replace the image and make sure the layer mask goes with it and you should be all set! Zipped PSD file is at 2560x1600.
To be truthful it's been long enough that I don't know where all the stock came from. I think probably at least some of the images are likely to be non-commercial, I'm just not sure.
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