Try the bounding box. It's simple:
var leftPos = $("#element")[0].getBoundingClientRect().left + $(window)['scrollLeft']();
var rightPos = $("#element")[0].getBoundingClientRect().right + $(window)['scrollLeft']();
var topPos = $("#element")[0].getBoundingClientRect().top + $(window)['scrollTop']();
var bottomPos= $("#element")[0].getBoundingClientRect().bottom + $(window)['scrollTop']();