Here are some commentaries that I have found exceptionally helpful.
On Matthew I go to Bruner’s 2 volume commentary (Vol 1 & Vol 2) and if I want something way more technical I check out Davies and Allison 3 volumes in the ICC. Here is a link to their “shorter commentary” that is an edited down version of those three 3 volumes.
For Luke, Bock is your guy. He has written extensively on Luke with the most thorough being his 2 volumes in Baker. Following Bock is Joel Green’s commentary in the NICNT (New International Commentary on the New Testament).
The Gospel According to John by D.A. Carson (Pillar) – I purchased this in grad school and it is still my “go to” commentary on John.
The Gospel of John: A Commentary by Bruner – I am tempted to rank this one higher than Carson first because it has the best sub-heading in the history of commentaries and second because it is just that good. The insights are fantastic and I cannot imagine studying John without this book.
Acts: An Exegetical Commentary (Baker – 4 volumes) by Keener – I have to admit that I have not read all umpteen zillion pages of this commentary but I have worked through the first three volumes when I preached through Acts last year. I believe this set will stand the test of time as the must have commentary on the book of Acts. It is very expensive to get all four and the research is extensive. So if you need something simpler on Acts go with Acts: A Shorter Commentary by C.K. Barrett. If you just want the gist and some important connecting pieces in the narrative go with Reading Acts by Talbert.
Romans (Hermeneia) by Jewett – I believe this is the best single volume commentary on Acts around. It is expensive so if you want to go a bit less expensive go with Cranfield’s “Shorter Commentary” on Romans. If you are struggling through Romans 9-11 check out Paul and the Faithfulness of God by N.T. Wright. If you want a comprehensive, multi-volume works that incorporates the New Perspective on Paul go with Dunn’s 2 volume commentary in Word.
When it comes to 1-2 Corinthians I go to Ben Witherington’s commentary on both books in 1 volume.
Another commentary that I go to frequently is Peter O’Brien’s Ephesians commentary in the Pillar series as well as his Colossians & Philemon commentary in Word. The Word commentaries are more technical and require more knowledge of Greek than the Pillar commentaries.
If you are studying the Pastorals check out Towner in NICNT.
The best Hebrews commentary is Attridge’s stand out commentary in Hermeneia. Again, those are expensive commentaries but worth every penny! If you are looking for something solid and scholarly but less expensive go with F.F. Bruce in the NICNT. If you want a great Hebrews commentary from a preacher, geared toward preaching check out Tom Long’s Hebrews commentary in Interpretation. It is very, very good.
On James my first stop is Luke Timothy Johnson in Anchor Bible. I am indebted to him for helping me iron out the James/Paul works/faith component in James. McKnight also has an excellent commentary in the NICNT series that you will want to consider.
Try out John Elliot in Anchor on 1 Peter. Talk about thorough. I have used it often and he never disappoints.
Revelation is always a tricky one. I have used a few commentaries on Revelation that I have really enjoyed so I will toss a few out there and give various reasons to go to each one. Reddish’s commentary is a very well balanced commentary that is good for just general study as is Mounce’s volume in NICNT. If you want to dig deeper than Reddish you will want to go with one of three options and I will list them in order of how technical they are (read that how much Greek you need to know) from least technical to most: Osborne in Baker, Aune’s 3 volume commentary in Word and Beale NIGTC (those last two are both highly technical).