Watch this video I got of a one legged Palm Warbler at Ackerman Park. Ackerman Park is part of the Celery Fields in Sarasota, Florida. I saw this little guy hopping around and noticed that he only had one leg. He seemed to be getting along just fine. He was in the same spot for many days. I would always look for him when I would come to this park. You can tell a Palm Warbler right away from the yellow on it's undertail. They also tend to pump their tails up and down. The Palm Warbler forages more on the ground than most warblers.
I didn't have any still pictures of a Palm Warbler myself, so I found this one on iBird Pro with the appropriate credit. You can see the yellow under it's tail.
Enjoy!