US Air Force Air Power Directory by David Donald
This book is the most accurate and complete listing off all Air Force units. World Air Power Journal has the best photographers in the business and the book is very easy to follow. All units, weaponry, tail codes, whatever you wish to find is included here. The only down side to the book is that is was printed pre-base closings, realignments. It was printed right when realignments were happening and it did have some inside information on who was closing and who was relocating.