Adsvert.com is a beautifully designed web interface. It sports a novel 3D menu system that [for once] is a pleasure to drive. There are a number of applications you can download and some online graphics engines that are capable of rendering instant composites of blueprints, insects or urban aligned image banks.
Here is a sample I whipped up from the blueprints generator. There doesn’t seem to be a save function so just hit printscreen and paste into your graphics program to crop.
linkage: graphics generator on adsvert.com