11-05-2011, 03:28 AM
do a search on flickr, however go to advanced and select creative commons, commercial to adapt, then do a search, write down the name of the contributing photographers, and then download the images you require.
When you complete the piece write to all the photographers with a link to your image, and thank them for there help and generosity.
CG Textures, Morgue file, google images,
Plenty of stuff out there, also think outside of the box, look for modern buildings that have egyptian columns, amusement parks, museums, look at antartica and the artic, quick colour change from white to sandy colour you have dunes,
Morrocco, kazaksthan, even australia has dune reference, Dubai, Saudi have dunes,
as for skies if you have a digital camera and can be prepared to do this yourself set the white balance to fluoroescent and photograph a sunset, the camera will make it even redder,