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 have a JButton in a JToolBar. Regardless of where the JButton is, you can give it an action listener with myButton.addActionListener and then in the action listener you tell the application what to do when the button is pressed.