The pics..
http://seaborg.nmu.edu/Clouds/CloudPix.html
http://bellabonalux.com/picturesofclouds.htm
http://www.photovault.com/search/res...l&pid=1&rpp=25
http://www.bushveld.co.za/pictures-clouds.htm
http://www.dramainnature.com/photogr...atic_light.htm

And descriptions of different types of clouds..
http://seaborg.nmu.edu/Clouds/default.html