This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
If you're at the point where you're just trying to get javac to run, then it's best to not set CLASSPATH to anything at all! It is not necessary to set it. Java will work fine with the default setting -- but setting CLASSPATH incorrectly will prevent it from doing anything.