Zorich writes "Scholars spend huge amounts of time and large sums of (often their own) money licensing images for their publications" and "the scenario will only worsen with the transition to online publication because the default rights environment is international in scope."
Images and Copyright
You must obtain the permission of the copyright holder of an image before using, reproducing, or manipulating it in an assignment or research paper. It is a good idea to verify whether you have permission to use an image before including it in your work, rather than saving this step for last.
When dealing with freely viewable collections on the internet, look for a page with copyright information, a license statement, terms and conditions, or permissions. This page may give blanket permission for educational purposes, instruct you to check copyright terms for each image, or ask that you contact the image owner for permission to use it. In other cases, you may be required to pay a usage fee.
Creative Commons Licenses:
A growing number of online images are being published with Creative Commons licenses (for example, many of the images on Flickr and Wikimedia Commons). These licenses are designed to give copyright holders a range of permission options for digital intellectual property and in most cases allow educational uses.
Particularly if you would like to alter an image or incoporate elements of it into a new art work, you should examine the license for details of how you are allowed to use the image. To see the license, click on the Creative Commons logo or the Creative Commons License link.
You will sometimes see images described as being "in the public domain." This refers to works that belong to the community at large, are not protected by copyright, and may be appropriated by anyone. For example, in Canada, most works pass into the public domain after fifty years following the end of the calendar year in which the author died. However, it is important to realize that while a work may be in the public domain, a specific edition or image of the work may be under copyright. http://www.lib.sfu.ca/help/publication-types/online-images#copyright
Using the Four Factor Fair Use Test by Gloria Harper (UT Austin)
Washington's Guidelines for Image Use on the Web
Duke University's How to Judge a Good Image
ALA's Internet Resources Index (by topic)
Links to past Internet Resources columns from College & Research Libraries News, listed by topic.
Copyright free images
Art Images for College Teaching AICT is a royalty-free image exchange resource for the educational community. Features images organized by time periods (Ancient, Medieval, Renaissance and Baroque, 18th-20th centuries and Non-Western. These images are royalty and copyright free and can readily be used for academic purposes.