Free textures:

http://www.freephotoshop.com/html/free_textures.html

13 Graphicxtras textures.

http://www.spectralogue.com/textures/index.php

Animals, space, wood, nature, metal, rock, cement, nature, fabric, 3D, people.

http://www.imageafter.com/textures.php

Nature, paintings, elements, glass, marbles, plastics and many others.

http://www.textureking.com/

260 free stock textures that can be used in photoshop. Liquids, grunge, concrete, plaster, metals, stone, rock, plant, wood, paint, rubber.