Where librarians and the internet meet: internet searching, Web 2.0 resources, search engines and their development. These are my personal views and not those of CILIP or any other organisation I may be associated with.
If you are in need of clip art that you can freely use without worrying about copyright restrictions, the latest site that I've found is the Clip Art Lord website. It's fairly basic, but it does have some nice images that you can use, and they do explain very clearly where the item has come from. To be fair, it's not overbrimming with images, but you may strike lucky.