Read these reference (encyclopedia) articles to get an overview of east Asian architecture throughout history.
The above articles are from: Stanton, A. L., Elliott, C. M., Seybolt, P. J., & Ramsamy, D. E. (2012). Cultural sociology of the Middle East, Asia, and Africa: An encyclopedia. Thousand Oaks: SAGE Publications, Inc.
Books on Chinese architecture:
Books on Japanese architecture:
Books on Korean architecture: