There are very few oustanding commentaries on this book, especially compared with the riches that are about to come out in the next ten years or so. Even so, there are a few good ones.
First-rate: Barrett (probably the single best), Alexander, Bruce, Fitzmyer, Haenchen, Marshall, Witherington, Larkin, Johnson, Longenecker. Get also the Marshall edited volume Witness to the Gospel. One should also get Dennis Johnson’s book The Message of Acts.
Second-rate: Conzelmann, Willimon, Polhill, Fernando, Gloag (op), Pelikan
Forthcoming: Bock (BECNT), Green (NICNT), Porter (NIGTC), Keener, Longenecker (revision), Pervo (Herm), Walton (WBC), Petersen (PNTC), Holladay (NTL)
Conservative: Alexander, Bruce, Larkin, Longenecker, D. Johnson, Polhill, Fernando, Gloag, Blaiklock
Moderate: Barrett, Fitzmyer, Marshall, Witherington, Johnson, Willimon, Pelikan
Liberal: Haenchen, Conzelmann