Paint My Photo. This is a wonderful site that has all sorts of copyright free photographs for people to paint. They actually want you paint the photos rather than charging you $200 or more to paint one!
iStock Phots etc
It's nice for a challenge like this one where I paint everyday and sometimes my own photos just don't float my boat that day. All they ask is that you try to post the link the original photograph from the site. I have been searching for this link and I can't seem to find it. But I will be more careful for any ones that I post in the future from this wonderful and very generous site!
Here is the original photo.