In A Long Way Gone, Ishmael Beah writes about his life in Sierra Leon in the mid 1990s. After being forced from his home by war, he ends up spending two teenage years as a solider in the civil war. About half the book though is about his rehabilitation and what happens to him after the war; it could be a lot more graphic than it is, although it's still plenty violent.
I particularly enjoyed this book after reading The Devil That Danced on the Water and Ancestor Stones, both of which are by Aminatta Forna and about Sierra Leon. (If you're looking for fiction about Africa, I highly recommend Ancestor Stones.) Forna's Devil covers earlier history, but gives a little background into the conflict that steals Beah's childhood. And the timeline at the end of Beah's book is very useful.
There are better writers out there (it's rather slow in parts, especially the beginning), but Beah still tells a good story. I'd like to hear his tale in person. Recommended.