Federal Court Locator
Links to sites containing full text of federal and state materials.

Judicial Opinions
Provides clear overview of decisions available electronically. Arranged hierachically covering US Supreme Court, Court of Appeals and State Courts.

State Court Directory
A directory which provides information regarding the availability of judicial opinions for each state.

On the Docket
Northwestern University's Medill School of Journalism site covers cases pending before the US Supreme Court

Supreme Court Decisions
Acccess to the full-text of US Supreme court decisions is provided by a number of sites:
Official Supreme Court site launched in April 2000 has opinions from 1999 with limited access to earlier opinions via gpo access. There is also a guide on where to obtain offical and unoffical copies of decisions. Decisions are posted on the same day they are delivered. This site also has orders, court rules, case handling guides and background information about the court;
Legal Information Institute at Cornell Law School (Decisions since 1990);
Fedworld/FLITE (1937 to 1975) ;
FindLaw (Decisions since 1893) ;
USSCplus (offers a variety of fee-based and some free services)

PreCYdent
This website is currently being developed but is a comprehensive site that allows users to find caselaw, statutes, GPO and lawyers amongst other things.  It contains US Supreme Court, Federal Reporter, Federal Circuit Court of Appeals and Federal District Courts cases from varying dates.