Where can I find briefs from legal cases? Can I find amicus briefs?
The best place to start is the database
Making of Modern Law: U.S. Supreme Court Records and Briefs, 1832-1978 A digital collection of more than 240,000 documents on more than 100,000 U.S. Supreme Court cases. It is a valuable database of primary source documents, as well as material presenting the background and context of the cases. This collection covers the Supreme Court from the final years of the fourth chief justice, John Marshall, through the first ten years of the court's 15th chief justice, Warren Earl Burger.