Except as noted, these and other books on the topic are generally found at the SLU Law Library, and are currently located on the fifth floor toward the North end, in the call number range KF5356 - KF5753. Search the SLU Library catalog as well to locate materials in the Pius Library or the Law Library's off-site location.
Journal articles on administrative law can be found via the SLU Law Library catalog. Below are a sample of somewhat recent articles that I located by entering "administrative law" in the SLUth Search Plus search window under the Search tab (http://www.slu.edu/colleges/law/library/). You can then limit your search to Academic Journals under "Source Type" as well as narrowing the results by publication date and geography (e.g., to select United States only).
Epstein, Richard A. "The Perilous Position of the Rule of Law and the Administrative State." Harvard Journal of Law and Public Policy 36.1 (2013): 5-19. Web.
Farber, Daniel A. and O'Connell, Anne Joseph. "The Lost World of Administrative Law." Texas Law Review 92.5 (2014): 1137-1189. Web.
Heinzerling, Lisa. "The FDA's Plan B Fiasco: Lessons for Administrative Law." Georgetown Law Journal 102.4 (2014): 927-989. Web.
The Hill, a subsidiary of News Communications Inc., is a newspaper published in Washington, D.C. since 1994. The "Regulation" tab on its website (http://thehill.com/regulation) purports to cover "how legislation is being implemented by executive branch agencies" and offers a RSS feed:
The Penn Program on Regulation's RegBlog (http://www.regblog.org/) offers a Twitter feed: