Right to Privacy Websites
The Legal Information Institute of Cornell University Law School hosts the Congressional Research Service's Annotated Constitution, a highly useful source for studying the Constitution. Privacy rights are discussed in several sections; you might begin with the introduction linked here.
Oyez, a searchable database of United States Supreme Court cases, is an excellent source for studying American legal history. The site provides efficient case summaries, audio files of the oral arguments, and links to written opinions.