I just got into wiring some of those myself. It's really easy if you have a soldering iron. You might be able to use some of that liquid solder stuff in a tube if you don't. I've never used the stuff, but I guess it works like some sort of metallic glue. I went to Radio Shack and got a variety pack of LEDs, red and green mixed. I think there's about 16 or so in there for about $3. Then I got a pack of 9-volt battery wiring packs. 5 for $2. Next you need a pack of 270 ohm resistors, 5 for $1. I had some spare 22 gage wire and solder so I don't know what that costs. 9-volt batteries are about $10 for 4. Can probably get those cheaper at Walmart.

Here's how to wire a pair of eyes.
1. Solder the red wire from the battery pack to one end of a resistor. Works either way.
2. Then solder the other end of the resistor to the positive wire on one of the LEDs, should be the longer one.
3. Now solder a piece of wire from the negative wire on that first LED to the positive wire on the second LED. Make it as long as you need to space your eyes.
4. Solder the black wire from the battery pack to the negative wire on the second LED.
5. Plug in a battery and you're done.

***Trick or treat. Smell my feet. Give me something good to eat.***