Here are two usefull little scripts. The first script is a function that will give you the full screen coordinates (not just the hot spot) for a given image.
The second script is a command that uses the first script to restrict the search region of your script based on an image name. It also takes an optional integer “fudge factor” by which to increase the search area by that amount in each direction. After calling this script be sure to return the search rectangle to full screen when you are finished by calling