If you want a good natural bar, give these a try:
http://www.prolithic.com/hpages/efoods/larabar.html
They are all natural, vegan, and delicious. They have 2-3 ingredients, for example the Cherry Pie has cherries, dates, and almonds. That’s it. No preservatives or other questionable ingredients.
They are a little on the spendy side at my LBS - $1.79 per bar, looks to be the same or more online. But quite tasty!
~geek