Legal decisions available from these websites are examples of the "Invisible Web", websites that cannot be easily located. Legal decisions are archived in online databases that search engines cannot index. When searching for legal decisions, it is useful to find out which agency or court adjudicates the decisions you are looking for and then check out that website. Unfortunately, many court cases, especially those from the lower courts, are still not available outside of fee-based (and expensive) databases such as Lexis and Westlaw.
U.S. Supreme Court and U.S. Court of Appeals decision are widely available on the Internet. Availability of other federal and state court decisions varies widely. For links to what is available (at no cost) on the Internet, start with the Court Opinions option on the Legal Information Institute home page: http://www.law.cornell.edu