Today, you will have an opportunity to pick up Stephen Nichol’s excellent book, Martin Luther: A Guided Tour of His Life and Thought (2002) for $1.99.
Students of the Reformation will also want to pick up my new book, Bold Reformer: Celebrating the Gospel-Centered Convictions of Martin Luther. Here’s a brief sample: 
The Protestant Reformers were men of unbending principle. They were men of unyielding conviction. These men fought relentlessly for the truth. Some of the battle took place privately as godly men wrote books and treatises, which magnified the mighty work of the gospel. Much of the battle, however, took place in public as the reformers made their bold ascent into the pulpit. Lines were drawn, the Word of God was declared, and lives were forever changed.
Oh, that we would recover the spirit of the Protestant Reformers in our day. May our pulpits reflect the great truths that Luther boldly proclaimed. May the great Name of Jesus be exalted in our generation.
Soli Deo gloria!
Veritas et Lux 