The CITE Journal had a recent special issue devoted to TPACK. You can access the special issue (edited by Judi Harris and Matt Koehler) here or individual articles below.
Bull, G., & Bell, L. (2009). TPACK: A framework for the CITE Journal. Contemporary Issues in Technology and Teacher Education, 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/editorial/article1.cfm
Niess, M. L., Ronau, R. N., Shafer, K. G., Driskell, S. O., Harper S. R., Johnston, C., Browning, C., Özgün-Koca, S. A., & Kersaint, G. (2009). Mathematics teacher TPACK standards and development model. Contemporary Issues in Technology and Teacher Education [Online serial], 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/mathematics/article1.cfm
Guzey, S. S., & Roehrig, G. H. (2009). Teaching science with technology: Case studies of science teachers’ development of technology, pedagogy, and content knowledge. Contemporary Issues in Technology and Teacher Education, 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/science/article1.cfm
Brush, T., & Saye, J. W. (2009). Strategies for Preparing Preservice Social Studies Teachers to Integrate Technology Effectively: Models and Practices. Contemporary Issues in Technology and Teacher Education [Online serial], 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/socialstudies/article1.cfm
Koehler, M. J., & Mishra, P. (2009). What is technological pedagogical content knowledge? Contemporary Issues in Technology and Teacher Education, 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/general/article1.cfm
Archambault, L., & Crippen, K. (2009). Examining TPACK among K-12 online distance educators in the United States Contemporary Issues in Technology and Teacher Education, 9(1). Retrieved from http://www.citejournal.org/vol9/iss1/general/article2.cfm