Verse-by-Verse Commentaries:

Roland K. Harrison, Numbers, Baker, 1990.
Arie Noordtzij, Numbers (Bible Student's Commentary), Zondervan, 1982. ***1/2
Dennis T. Olson,
Numbers (Interpretation), Westminster John Knox, 1996.
Elmer Smick, "Numbers" in
The Wycliffe Bible Commentary, The Southwestern Company, 1968.
Gordon J. Wenham,
Numbers (Tyndale), 1981.****

Monographs, Compilations, and Studies:

Dennis T. Olson, Death of Old and Birth of New: Framework of Numbers and the Pentateuch (Brown Judaic Studies Series)
____ Scholars Press, 1985.****
Gordon J. Wenham, Numbers (Old Testament Guides), Sheffield, 1997.

Articles and Essays:

Walter J. Harrelson, "Guidance in the Wilderness: The Theology of Numbers," Interpretation 13 (1959): 24-36.
Dean R. Ulrich, "The Framing Function of the Narratives about Zelophehad's Daughters,"
JETS 41 (1998): 529-538.

More Commentaries of Interest:

Timothy R. Ashley, The Book of Numbers (NICOT), Eerdmans, 1993.
Thomas B. Dozeman, "Numbers" in The New Interpreter's Bible, vol. II, Abingdon, 1998.
Baruch A. Levine, Numbers 1-20 (Anchor), Doubleday, 1993-. (2 vols.)
Jacob Milgrom, Numbers (JPS Torah Commentary), Jewish Publication Society, 1990.***1/2
Eryl W. Davies, Numbers (New Century), Eerdmans, 1996.

More Monographs

More Articles:

Robert C. Culley, "Five Tales of Punishment in th Book of Numbers" in Text and Tradition: The Hebrew Bible and Fokelore
____ (SBL Semeia Studies) ed. S. Niditch, Scholars Press, 1990: 25-34.