We are often asked in CAIeROs where to obtain images that are licensed for use in material that could be part of an Open Resource. There is nothing worse than having to pick out images from a potential OER because of copyright problems. This article on Zembl is a really useful guide to where you can find suitable images.
http://zembl.com/news/blogs/2013/11/15-places-get-free-images-your-elearning
