Administrative Law most often takes the form of rules or regulations, but it can also consist of other administrative actions such as decisions or orders. Although agencies are considered part of the executive branch, the duties that agencies perform are similar to the functions that we associate with all 3 branches of government. Rulemaking and regulations are part of the "legislative" role of agencies. Here is a look at the 2 other roles of agencies.
For additional insight into administrative decisions, check out this article from Student Lawyer magazine by Shawn Nevers.
Student Lawyer, Vol. 40, No. 4, pp. 21-22, December 2011
In their judicial role, federal agencies can adjudicate controversies arising out of the violation or interpretation of statutes and administrative regulations. There are a variety of formats that these adjudications can take including hearings before special boards of review, hearing examiners, other officers or administrative law judges.
The publication of administrative decisions is more fragmented than rules and regulations, and there is no one place where all such decisions are located. Some agencies will have a their own reporter with a name like the ICC Reports or the FCC 2d where their adjudications are published. Most agencies now publish their decisions on their website, but see Bluebook’s Table 1.2 for a list of official sources of agency decisions.
Practitioners who work in a highly regulated area of law generally use a commercial service such as BNA or CCH that provides access to relevant primary law, including cases, statutes and regulations, as well as administrative decisions and other analytical materials.
In their executive role, agencies enforce the law by inspecting regulated parties and facilities, issuing orders or licenses and assigning fines or penalties. For example, the Environmental Protection Agency inspects facilities and monitors pollution levels, the Federal Communications Commission issues licenses to operate radio stations and the Nuclear Regulatory Commission issues permits and monitors the operation of nuclear energy facilities.
These functions vary greatly in name and purpose from one agency to another. The best source for information regarding an agency's enforcement actions is that agency’s website. It will generally contain information regarding that agencies regulations and also guides for working with the agency.