I had once seen a post that had very simple instructions for a 5V powersupply off of a wall wart using a 7508 reg. two capacitors and a resistor with an led on a bread board... can anyone point me in the right direction to find it again?
It's a 7805 (not 7508), and any 7805 datasheet will have an example circuit. Looking at the front of the device the pins are Vin, GND, Vout. A 10uF electrolytic capacitor between Vin and GND and a 1uF cap between Vout and GND are the most common values.
The LED is just a power-on indicator, and the LED sets the current for the LED. It's probably 330 to 470 ohms.
sorry, don't have a schematic.
-j
Here's another version like the one you described with the breadboard.
http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=57
You have to scroll down a little to get to the power supply part.