In addition to regulations, agencies publish lots of good research materials. While anything outside of regulations (and sometimes authorized adjudication,) is not the law itself, agency materials have a high persuasive value. The type of materials, depth of materials, and ease of access of materials can vary greatly among agencies. Once you have identified a topic it is a good idea to spend a little time perusing the websites of relevant agencies.
For federal agencies you might try:
Law Reviews & Journals are also a good way to start familiarizing yourself with a topic area. Below is a list of some topical law and non-law journals which may assist you. If you need help locating an article try using the catalog instructions above or ask for help at the reference desk.
Blogs are a great place to get started with topic selection or to get a pulse on the current conversation.
Below is a list of some blogs to get you started.
If you want to track relevant news stories then check out these links as a good starting point.