I found that even the ones claiming to be high in protein were also high in fat and carbs, except for the one brand of bar.

That's not too surprising. Except for the people on special diets, most energy bars are designed for athletes looking for a pre/mid/post-workout snack, and the best fuel for that situation is carbs, since that's what replenishes your muscles' energy. The only reason you see any protein in these bars at all is because in recent years, it's been "discovered" that eating carbs isn't enough for muscle recovery after/during exercise. In order to help rebuild (and strengthen) all those muscle fibres that have been broken down through exercise, the body also requires some protein, which is what those fibres are made of. Without the protein, your muscles get energy, but they don't start to rebuild as quickly. As a result, energy food makers started adding protein to the mix, and "high protein" on a label usually equates to "more than none."

If you've just been looking in a regular supermarket, you might have better luck finding something in a health food store, or a Trader Joes.

Disclaimer: I'm not a nutritionist or medical person by any stretch of the imagination (but I took a nutrition course in university). This is all just stuff I've picked up from reading various literature and trying to find something that tastes better than PowerBars, but works just as well. Corrections from those who know are welcome.