Foxnews has an article on the skeletal remains of an aquatic lizard that had only nubs for front limbs, filling in the link between these animals and the snakes that followed them. Quotes the story:
"It adds to the picture we have of what was happening 100 million years ago," said lead researcher Michael Caldwell, a paleontologist at the University of Alberta. "We now know that losing limbs isn't a new thing and that lizards were doing it much earlier than we originally thought."
Odd questions remains, though.
"For some oddball reason, the forelimbs were lost before the rear limbs, when you would think it would be the opposite," Caldwell said. "The front limbs would be useful for holding onto dinner or digging a hole, but it must be developmentally easier to get rid of the forelimbs."
Still, this is a good example of a transitional form and at least one evolutionary path that lizards went down.