After many great reads on Church history combined with an exhaustive study of this subject in school since I was a child, I'd have to say these are some good starter books on the road to becoming an expert in Church history.
1. The Church History by Eusebius/Maier
2. Search for the Twelve Apostles by McBirnie
3. The Lost History of Christianity by Jenkins
4. The 100 Most Important Events in Christian History by Lang/Peterson/Curtis
5. 70 Great Christians by Hanks