If you have objects in your drawing that overlap each other, or even if they are very close, there is an easy way to cycle through those objects and select the desired one.  When you are at the select objects prompt in any AutoCAD command just hold down the Ctrl key while picking the objects.  With each left click of the mouse AutoCAD will cycle to, and highlight, the next object.  Once the desired object is highlighted just press the enter key and continue with the command.