This category of books includes reference works for all of us archaeo-nuts, including encyclopedias and overviews, biographies and histories of archaeology, and travel references.
Biographies and History of the Discipline
I love a good biography, and fortunately there have been several good biographies of archaeologists in the last few years. Also in this class of book are lumped histories of archaeology.

Digging through Darkness
Finding the Walls of Troy
Grahame Clarke: An Intellectual Biography
The Land of Prehistory
Conversations with Lew Binford
Bandelier: The Life and Adventures of Adolph Bandelier
Encyclopedias and Overviews
This category is made up of my professional secret stash of encyclopedias and overviews. While supplemented by frequent trips to the library, this group is still the backbone of the Archaeology website at About.com, and is guaranteed to help anyone get familiar with a broad bariety of topics.

The Oxford Companion to Archaeology
Archaeology of Ancient Mexico and Central America
Medieval Archaeology
The Archaeology of Mainland Southeast Asia
Prehistoric Europe: An Illustrated History
Prehistory of Australia
Prehistory of the Indo-Malaysian Archipelago
Aspects of African Archaeology
Travel Guides
I don't know of very many of these guides, but I certainly appreciate the fact that they exist! Look for more to appear here in the future.

Southern France
Greece