Pain and Suffering

Here are some good explanations that I have found to explain the pain and suffering that are in the world.

ChristianAnswers.net:  Why Does God Allow Innocent People to Suffer?

CERC:  Based on C.S. Lewis' The Problem of Pain

Zacharias, Ravi:  Problem of Evil

Keller, Tim:  The Problem of Evil and Suffering, Part 1
     The Problem of Evil and Suffering, Part 2
     The Problem of Evil and Suffering, Part 3
     The Problem of Evil and Suffering, Part 4
Koukle, Greg:  Why Does God Allow Evil and Suffering?