So let's have ourselves a list of books that are generally archaeologically awesome ...
Roman Art and Archaeology
Rome: An Oxford Archaeological Guide to Rome - A Claridge.
This book is fasntastic. It gives an overview of all the extant monuments of the city of Rome (which is perfect if you're visiting it or studying it). Some of the opinions can be a little outdated, but Claridge often updates the book. It also pairs well with F. Coarelli's Environs of Rome.
Roman Sculpture - D. Kleiner.
For anything on Roman art/sculpture, this is the first book to look at. It gives not only a solid overview of all the imperial portraiture of the Roman emperors (from Caesar through to Constantine), and their major monuments, but also summaries of private portraiture and funerary sculpture. There are plenty of examples and summaries of the main scholarly debate for each piece.
Roman Art and Imperial Policy - N. Hannestad.
Each period (Julio-Claudians to Constantine) is treated dynastically and appears to be of the same school of thought as Zanker (see below). Once again there are numerous examples for each period, including architecture as well as art, with a particular emphasis on the propaganda of each generation.
The Power of Images in the Age of Augustus - P. Zanker.
Although the concept of 'imperial propaganda' is firmly rooted in the political situation of the 1980s and 1990s, this book is still an interesting read today and gives quite a pleasing interpretation of the period, not to mention having invaluable examples from the early Julio-Claudian principates.
Principles of Roman Architecture - M. Wilson Jones.
Perfect for a more in-depth study of Roman architecture, with particular attention to the orders and includes an excellent case study of the Pantheon, including more modern interpretations and geometric principles of planning. Wilson Jones takes Vitruvian principles of Roman architecture and applies them practically. This also works well with F. Sear's Roman Architecture and B. Ward-Perkins' Roman Imperial Architecture.
That'll do for now, kids ...