go to Paint (or your favorite drawing program) select and copy the image (this puts the image onto the clipboard), go to labview and paste the picture on the front panel.
You can also attach an image to a control (like a button) by right clicking the fP object, selecting Advanced >> Customize, and (in the control editor that is launched) right click the object and select import picture. This method is nice because you can import one image for the true state, and another image for the false state. I've used this method for small push buttons to show that the button was pressed. For example, for a Load button, you might have the traditional windows load icon (a folder) and when you press the button, the folder opens.