And not just robots, scavenging from most electronic equipment will give you a range of parts to get you started. I've taken appart VCRs in the past which give you a few motors, possibly some LEDs, a whole range of components (if you're willing to desolder them from the PCB) not to mention screws, gears and metal/plastic from the case itself. Here is and example of a robot build completely from scrounged parts.

In addition to Radio Shack or your local equivalent (RS Components and Maplin here in Scotland) there are a whole host of online shops for electronic components and robotic equipment. Solarbotics would be an example of the later.

markcra.com

I would reconmend ACE HARDWARE thats were Mark tilden went to make the robospaien, Just check out the robosapien evalution fourm.

"One man can change the world, but it takes all of mankind to save it" -Josiah Mendez-