I began reading Francis Collins' The Language of God. For anyone interested in Dawkins's God Delusion, Collins is must reading. Dawkins drops his jaw in wonder at the idea a brilliant biologist such as Collins who turned from atheism to theism.
In Collins's first chapter he writes of his conversion from atheism to theism as largely the result of readin C.S. Lewis's Mere Christianity and being impacted by Lewis's argument for God on the basis of the innate Moral Law.
Especially interesting is when Collins writes how the Moral Law cannot be explained by evolutionary processes.