i make my own using
oats
nuts, either peanuts or almonds or both, depends whats in the pantry at the time
bananas
chocolate whey powder
peanut butter
and some milk or water to bring it all together (not much is needed only about 2 tablespoons or so)
use a food processor, and then mix everything in a large bowl, then flaten out into a tin of some sort, wrap and freeze for a few hours.
then take it out of the freezer and cut up into individual bars, wrap in cling wrap, and then back into the freezer. eat as needed
i get about 20 bars every time i do this, it's alot cheaper than buying them and alot better for you, as you can control whats in them....