You're in luck, there's a super simple method to this! You can find the material here. Now, for technique, first drill your hole, (not too deep, not too shallow, you can make a reasonable guess as this is pretty easy. http://www.projectguitar.com/uploads/emoticons/default_biggrin.png' alt=':D'>) Now use a bit of cyanacrylite (superglue) into the hole of question. The next step is to poke that plastic rod into the hole, cut off the excess, sand etc.
Thats it!
Edit: You could use epoxy as well, epoxy with black pigment works well for ebony fretboards, but as long as you drill the hole the right size it doesnt matter what glue you use.