A program like Gaim or Kopete has an option to put an icon in the system tray. Also, in the configuration look for an option to connect when you start, as well as to start minimized.
For other programs, if they are on the KMenu, you can simply click and drag the icon from the Kmenu and drop it on either the panel or the desktop.
After dropping an Icon on the Desktop or Panel, right click on the icon. Click on Properties, and then the Application tab. Under Advanced options, you can select some features such as to place an icon in the system tray. This allows you to pop it up instantly by clicking on the icon in the system tray. I have a konsole icon on the right hand side of the panel as well as the left. The left on is set up to run as root, so I can click it, enter the root password, and then make the configuration changes I want to.