D. A. Carson's works 75% off at Logos

See the sale (expires in 15/4).
Personal recommendation:

• Commentary on the New Testament Use of the Old Testament (US$15 now)
• Exegetical Fallacies, Second Edition (US$4 now)
• Pillar New Testament Commentary: The Gospel according to John (US$11.5 now)
• An Introduction to the New Testament (US$8 now)
• The Gagging of God: Christianity Confronts Pluralism (US$7.5 now)

free audio book for April 2013

Free Audiobook of the month from christianaudio.com: 
  Andy Stanley, Enemies of the Heart Breaking Free from the Four Emotions That Control You . 

free Logos ebook for April 2013

Free ebook of the month from Logos: John Newton, The Works of John Newton, vol. 1 .