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.
You can use javac directly, so long as javac is in the path, i.e. linux knows what program you are on about when you type "javac" and where to find it. You can put your own packages anywhere, so long as you add them to your classpath when you run javac.