This is where a program such as the one Kato mentioned could be useful. Running pics through that has to make it a bit harder for anyone to prove copyright infringement.
Also, I'm fairly sure that if Paul was to ask for it, every last one of us would drown him in pics we've taken in the multitude of museums we've been to, exercises we been on, and private collections eyes have been laid upon.
Sifting through the torrent of pictures would be a bit of a challenge though....
