Knowledgebase Talk:Image and Texture Resources
3D Texture Libraries and Backgrounds from TextureWorld should be removed as it was a commercial texture selling site and its archive shows no reachable samples: http://web.archive.org/web/20080702135359/www.textureworld.com/Texture_Libraries/Store/
Area map search form can be updated to: http://geonames.usgs.gov/
(Have to check links between those two)
Texture Studio http://web.archive.org/web/20071110230039/studio.planethalflife.gamespy.com/textures.asp but I'm not sure files are any longer reachable from there (have to check)
Old Dreamsandmagic textures can be found here: http://web.archive.org/web/20001205185700/www.dreamsandmagic.com/freebies.htm
and a few free samples of the later commercial product here: http://web.archive.org/web/20030622175051/dreamsandmagic.com/cd2.htm
PBourke's Textures Archive seems to still be online and located here: http://local.wasp.uwa.edu.au/~pbourke/texture_colour/
The last link, USGS us DEM maps, needs to be updated to: http://eros.usgs.gov/#/Find_Data/Products_and_Data_Available/DEMs