Free database with information on more than 81,000 built and unrealized projects from architects and planners, mainly 20th century. International in scope. You can look up projects by architect, town, or keyword, and results are presented in a wiki-style form.

Buildings of the United States (BUS) is an award-winning series of books on architecture in the U.S. compiled and written on a state-by-state basis. The series is commissioned by the Society of Architectural Historians and published by University of Virginia Press.

Useful for any Chicago project. Includes a dictionary and building database.

Indispensible resource for scholars and students of literary theory and discourse.

Great starting point for finding essays, bibliographies, links to images.

Includes essays on architecture from a variety of places, cultures and period.

Full text books from many disciplines. Includes the Oxford Dictionary of Architecture and Landscape Architecture which covers Western architectural history. Includes essays, links and bibliographies.

Includes essays, bibliographies and links for built works in California, Oregon and Washington.

Histories, photographs, and maps for more than 2000 structures in 710 cities and 20 states in the US selected by the Society of Architectural Historians (SAH).