http://www.cgtextures.com/
Absolutely incredible site for textures of every kind imaginable!
The huge numbers of just the concrete variations is mind-boggling and then there is the almost limitless road surfaces . . . and the list goes on and on - including background scenery, WOW!
It's a modeler's dream site for all those surfaces we would love to have, but have no skills to reproduce by hand. MAGIC!
This should be on everyone's source list for online help.
Thanks for posting it, Paul. It is inspirational.