Government agency websites are important. They may provide guidelines for implementing regulations, required regulatory filings, and administrative decisions.
Agency websites can be chock full of information - for free! Although you have unlimited access to useful databases as law students, that is unlikely to be the case as an attorney, particularly outside of high-paying firm jobs. Some government agencies will provide some level of access, depending on their own budgets and needs. Be aware that there are free places to find statutes, regulations, and administrative decisions outside of Westlaw and Lexis. The EPA provides online access to relevant laws, regulations, and policy guidance documents. There is a web portal specifically for the Environmental Appeals Board with dockets, decisions, guidance documents, recent actions, etc.
You might find information you did not know existed - and was very helpful! This could be useful for school research, practicing, or even in preparing for interviews. For example, the Environmental and Natural Resources Division of the Department of Justice has a monthly newsletter on environmental crimes designed to help practitioners keep up with recent developments.
You can find practice resources - that are updated faster than subscription databases! Practicing or researching an area of the law does not stop at the regulations. There are rules on practicing before a particular body, rules for citation format, guidelines for rule implementation, etc. Some of these types of resources may be available online, but even if they are, the version on the website will likely be updated first. For example, the EPA has a practice manual (PDF download) for proceedings under an administrative law judge.
You can use Google - it is your friend! But be aware that it has limits. If you are looking for a specific document that is relatively frequently utilized, it is highly likely you will find it (and even from a reputable source). If you are looking for secondary sources, they will be more difficult to find on Google - partially because there are A LOT of them, but also because many are only available from subscription websites. Government documents can usually be found in this way, but it may take more digging on a government website. The ability to access government information also depends on the transparency and government publication laws of a particular state. When you are doing general research on Google, rather than searching for a particular document, you should default to Google Scholar and use the advance search capabilities that will help you narrow your search.
When it comes to agency websites, not all of them are created equally - some are much easier to navigate than others. If you are going to be doing substantial amount of work with a particular agency, you should take the time to play around the website. Take advantage of any search options within the website.
SEARCH TIP: You can use Google search capabilities on only one website at a time by using Google Advanced Search.The interface is similar to advanced searching on any electronic database, so it should be easy to use. To search one website using the tool, enter the website in the "site or domain" box.