Galatians. REC. P&R Publishing, 2005.
Philip Ryken's commentary on Galatians is a must for bible teachers. Similar to the Preaching the Word series, Ryken focuses on passage guides rather than word for word exegesis. I found that to be very helpful and engrossing. Packed with illustrations and wisdom, I highly recommend this as a first purchase if you are studying or teaching Galatians.
Genesis: Beginning and Blessing. PtW. Crossway, 2004.
In typical fashion, R. Kent Hughes blends relevant application with solid exposition. Many commentaries on Genesis are filled with technical language that only benefits a few. Hughes recognizes that most pastors and laypersons don't need the extra jargon, they just need the truth of God's Word presented in a way that challenges the lives of its hearers. This is a fantastic commentary for teachers of the Bible.