What follows is an an organized and curated list of content. Click here for an exhaustive list of content on Joel
Homer Heater Jr.: 12. Joel  Part of a series on the Old Testament prophets. History, Background, Extensive paragraph outline.
Kenneth Boa: 37. Joel  Part of the series: Visual Survey of the Bible.
Bill McRae: 26. Hosea and Joel  Part of the Series: "Survey of the Bible"
Imanuel Christian: 38. The Book of Joel 
Mark Dever: Who Will God Save? The Message of Joel  Capitol Hill Baptist Church
Ray Stedman: Joel: The Revelation of God’s Hand [, , Translated] Part of the series: Adventuring Through the Bible. Peninsula Bible Church. Spanish translation available.
Mark Dever: Troubles  4 part series. Capitol Hill Baptist Church.
S. Lewis Johnson: Joel [, ] 5 lessons.
John Piper: The Locust Horde and the Day of the Lord [, ] 1 lesson.
Study Helps and related
Tom Constable: Tom Constable’s Expository Notes on Joel  This is also available in the Net.Bible.org Study Environment.
David Malick: An Introduction to the Book of Joel 
An Argument of the Book of Joel 
Hampton Keathley IV: 2. Joel Part of the series: The Minor Prophets.
J. Hampton Keathley, III: 7. The Minor Prophets  Part of the series: Concise Old Testament Survey.
Tom Hawkins: 3. Joel: Introduction, Outline, and Argument