The Legislative Branch
Congress Congress' own website is the place to start looking for current legislation and the U.S. Code.
The Executive Branch
President of the United States Presidential signing statements and declarations are available here, as well as information of the Executive office of the President.
Government Agencies This is a list of U.S. administrative agencies. The sites for each individual agency are a great place to start looking for practical advice on interacting with the agencies. Administrative agencies cover a wide variety of areas of law and life in the United States, and many governmental benefits are obtained through applications or filings with them, instead of through courts.
The Judicial Branch
- Supreme Court The U.S. Supreme Court publishes their recent decisions on their website for free public access, making it a good resource for those who want current case law. Their archive of older cases is somewhat limited though.
- Federal Courts This site has links to the various Appellate Circuits, who hear appeals, and the U.S. District Courts, where trials are heard. The sites for each court are the best location for finding the local court rules, which can be used alongside the Federal Rules of Appellate Procedure, the Federal Rules of Civil Procedure, or the Federal Rules of Criminal Procedure to understand how to file a case.
- PACER Public Access to Court Electronic Records, or PACER, is a way of pulling records from court dockets to be read. There is limited free public usage on a quarterly basis, but litigants also get free access to their own case. Start here if you need to see what has been filed in a current case. but be aware that some documents may be redacted or sealed at the court's discretion.
Assorted
- Govinfo This is the clearing house for legislation, congressional materials, regulations, the US Code and Code of federal regulations, and much, much more.
- Library of Congress The library of Congress is a great resource for finding older materials, histories of various legal topics, and older U.S. Supreme Court cases.