I sympathize with your not finding a lot of interest in your lithographs here. The set is nice, but it's a difficult category in which to find buyers. While there are lots of fans of the Disney Villains, there aren't many people who collect them as a category. Most fans have a few favorite Disney films or characters that they collect, rather than the Villains or Princesses.
At this point, I think you'll be best off posting them on eBay. Good luck!