Dale Ralph Davis is widely regarded as one of the most gifted Old Testament expositors today. His commentaries on the Old Testament are treasures of expositional teaching.
Monergism has put together a collection of 15 sermons by Davis on the Psalms. If you’ve never heard Davis preach I can think of no better collection of sermons to begin with.
Prayer for a Dark Morning – Psalm 5:1-12
God’s Lullaby – Psalm 4:1-8
Praying on the Run – Psalm 3:1-8
God Is Mixed Up in Politics – Psalm 2:1-12
Thanksgiving in July – Psalm 116:1-19
When the Bad Guys Win – Psalm 73:1-28
When Everything Falls Apart – Psalm 11:1-7
Relief Begins with an “F” – Psalm 32:1-11
Teach Me the Patience of Unanswered Prayer – Psalm 88:1-18
The God Who Is There – Psalm 139:1-24
Amnesia and Praise Don’t Mix – Psalm 105:1-35
Faith – From Crying to Confidence – Psalm 13:1-6
Praying Among the Ruins – Psalm 74:1-23
A God To Be Thankful For – Psalm 104:1-35
A Few Years in God’s School – Psalm 2:11-25
Faith by Hearing 
Hey,
Wanted to quickly encourage you to keep up the good work :).
— Joshua