Verse-by-Verse Commentaries:

Craig Bartholemew, Reading Ecclesiastes (Analecta Biblica, 139), Editrice Pontifico Istituto Biblico, 1998.
Michael A. Eaton, Ecclesiastes: An Introduction and Commentary (Tyndale) InterVarsity Press, 1983.
Michael Fox, A Time to Tear Down and A Time to Build Up: A Rereading of Ecclesiastes, Eerdmans, 1999.
Ernst Hengstenberg, Commentary on Ecclesiastes, Wipf and Stock, 1998.
Derek Kidner, The Message of Ecclesiastes (The Bible Speaks Today), Inter-Varsity, 1976.
Roland Murphy,
Ecclesiastes (Word), Word Books, 1992.***1/2
Choon-Leong Seow, Ecclesiastes (Anchor), Doubleday, 1997.****

Monographs, Compilations, and Studies:

Eric S. Christianson, A Time to Tell: Narrative Strategies in Ecclesiastes (JSOT Sup, 280), Sheffield Academic, 1998.
Jacques Ellul, Reason for Being: A Meditation on Ecclesiastes, Eerdmans, 1990.
J. A. Loader, Polar Structures in the Book of Qohelet (BZAW, 152) Walter de Gruyter, 1979.
Antoon Schoors, The Preacher Sought to Find Pleasing Words: A Study in the Language of Qoheleth (Orientalia Lovaniensia
____ Analecta, 41), Peeters, 1992.****
Roy B. Zuck (ed.), Reflecting with Solomon, Baker, 1994.****

Articles and Essays:

Stephen G. Brown, "The Structure of Ecclesiastes," Evangelical Review of Theology14 (1990): 195-208.
Ardel B. Caneday, "Qoheleth: Enigmatic Pessimist Or Godly Sage," Grace Theological Journal 7 (1986): 21-56.
D. M. Clemens, "The Law of Sin and Death: Ecclesiastes and Genesis 1-3,"
Themelios (1994): 5-8.
Frederick Danker, "The Pessimism of Ecclesiastes," Concordia Theological Monthly 22 (1951): 9-32.

Meredith M. Kline
, "Is Qoheleth Unorthodox?" Kerux 13 (1998): .
Andrew G. Shead, "Ecclesiastes from the Outside In," Reformed Theological Journal 24 (1999): 24-37.
Carl Shank, "Qoheleth's World and Life View as Seen in His Recurring Phrases," WTJ 37 (1974): 57-73.
Dougals B. Miller, "Qohelet's Symbolic Use of Hebel," JBL 117 (1999): 437-454.
Danny Olinger, "Is Wisdom Literature Eschatological?"
Kerux 11 (1996).
Choon Leong Seow, "Qohelet's Eschatological Poem," JBL 24 118 (1999):.
________ "Qohelet's Autobiography" in Fortunate the Eyes that See
(ed. A. Beck, et al), Eerdmans, 1997.
Arian Verheij, "Paradise Retried: on Qohelet 2:4-6,"
JSOT (1991): 113-115.

More Commentaries of Interest:

George Aaron Barton, A Critical and Exegetical Commentary on the Book of Ecclesiastes (ICC), T & T Clark, 1909.
moderate mainline perspective; textual, linguistic, comparative value; thorough introduction; dated.

David Hubbard, Ecclesiastes, Song of Solomon (Mastering the Old Testament), Word Books, 1989.
Kathleen A. Farmer, Proverbs and Ecclesiastes: Who Knows What is Good? (ITC), Eerdmans, 1991.
Duane A. Garrett, Proverbs, Ecclesiastes, Song of Songs (New American Commentary), Broadman, 1993.
Trempor Longman III, The Book of Ecclesiastes (NICOT), Eerdmans, 1997.
Iain Provan, Ecclesiastes / Song of Songs (NIV Application Commentary), Zondervan, 2001.
Addison G. Wright, "Ecclesiastes (Qoheleth)" in The New Jerome Study Bible, Prentice Hall, 1990: 489-495.

More Monographs of Interest:

William H. U. Anderson, Qoheleth and Its Pessimistic Theology: Hermeneutical Struggles in Wisdom Literature, Mellen Biblical
____ Press, 1997.
Robert Gordis, Koheleth: The Man and His World, Schocken, 1969.
third edition; Gordis' work, originally published in Hebrew, has become the modern classic on Ecclesiastes.

More Articles of Interest:

William H. U. Anderson, "Philosophical Considerations in a Genre Analysis of Qoheleth," Vetus Testamentum 48 (1998): 289-300.
________ "The Curse of Work in Qoheleth: An Expose of Genesis 3:17-19 in Ecclesiastes," Evangelical Quarterly 70 (1998): 99-113.
________ "The Poetic Inclusio of Qoheleth in 1,2 and 12,8," Scandinavian Journal of the Old Testament 12 (1998): 203-213.
Michael Fox, "What Happens in Qohelet 4.13-16?"
Journal of the Hebrew Scriptures 1 (1997), art. 4.
Daniel C. Fredericks, "Chiasm and Parallel Structure in Qoheleth 5.9 - 6.9," JBL 108 (1989): 17-35.
________ "Life's Storms and Structural Unity in Qoheleth 11:1-12:8," JSOT 52 (1991): 95-114.
Walter Kaiser, "Integrating Wisdom Theology into Old Testament Theology: Ecclesiastes 3:10-15" in
A Tribute to Gleason Archer
____ (ed. J. Youngblood), Moody, 1986.
Oswald Loretz, "Poetry and Prose in the Book of Qohelet (1:1-3:22; 7:23-8;1; 9:6-10; 12:8-14)" in Verse in Ancient Near Eastern Prose
____ (Alter Orient und Altes Testament, 43) ed. Johannes C. de Moor and Wilfred G. E. Watson, Neukirchener Verlag, 1993: 155-189.
Gerald T. Shepherd, "The Epilogue to Qoheleth as Theological Commentary." Catholic Biblical Quarterly 39 (1977): 182-189.
Addison G. Wright, "The Riddle of the Sphinx: The Structure of Qohelet,"
CBQ (1968): 313-334.
________ "The Riddle of the Sphinx Revisited: Numerical Patterns in the Book of Qohelet,"
CBQ 42 (1980): 35-51.
________ "Additional Numerical Patterns in Qoheleth,
CBQ 45 (1983): 32-43.

James S. Reitman, "The Structure and Unity of Ecclesiastes," Bibliotheca Sacra 154 (1997): 297-319; 317-319.

Addison G. Wright, "The Poor but Wise Youth and the Old but Foolish King (Qoh 4:13-16)" in Wisdom, You are My Sister (ed. M. Barré), 1997: 142-154.