Holiest Of All Andrews Murray's devotional commentary on the Letter to the Hebrews is simply the best. I have used it as a standard text for 25 years.
The Epistle to the Hebrews (The New International Commentary on the New Testament) F. F. Bruce combines outstanding scholarship with powerful spiritual insights. This is a MUST read for students of Hebrews!
Hebrews (The Anchor Yale Bible Commentaries) This is one of the most worthwhile commentaries available on Hebrews. This is well worth the investment of your money and time.
Be Confident (Hebrews): Live by Faith, Not by Sight (The BE Series Commentary) An excellent devotional commentary in the acclaimed "Be..." series. An ideal commentary for use in your Sunday school class or Bible study group.
Hebrews (Tyndale New Testament Commentaries) This is a thoroughly readable, accessible and affordable introductory commentary to Hebrews. An ideal entry-level text to Hebrews scholarship.
Word Biblical Commentary Vol. 47a, Hebrews 1-8 In my opinion the Word Biblical Commentary series is one of the finest available. This outstanding volume covers the first 8 chapters of Hebrews.
Word Biblical Commentary, Vol. 47b, Hebrews 9-13 Volume 2 of Dr. Lane's outstanding commentary covering chapters 9-13.