Supreme court cases are available from many sources including the ones below. The best way to find a specific case is by citation (i.e. 347 U.S. 483). If you are looking for cases on a topic use Nexis Uni - select "Cases"from the the Guided Search, the jurisdiction and enter some keywords.
An Oral Argument is an oral presentation of a party's position before the court. Transcripts are available at:
A Brief is a formal written presentation of an argument that sets forth the main points with supporting evidence. Briefs are filed by both parties and often by "friends of the court" (amicus curiae). This term describes a person or organization that is not part of the lawsuit but has a strong interest in the case.