ho trovato con google.... :quipy:
codice:
<script type="text/javascript">
     // this function returns the x, y position
     // works in IE and Mozilla.
     function getElementPosition(element){
          var x=0,y=0;
          while (element!=null){
               x+=element.offsetLeft-element.scrollLeft;
               y+=element.offsetTop-element.scrollTop;
               element=element.offsetParent;
          }
          return {x:x,y:y};
     }
     // Browser compatible element getter
     function getElement(id){
          if (document.all)
               return document.all[id];
          if (document.getElementById(id))
               return document.getElementById(id);
          
          return null;
     }
     // generic display function
     function findElement(id){
          // Get the element by its id
          element = getElement(id);
          // make sure that the element was found
          if (! element) return;
          // get the object that will contain the x,y coordinates
          position = getElementPosition(element);
          // display the coordinates
          alert('x: ' + position.x + '\n\ny: ' + position.y);
     }
 
</script>