How do I select a layer "sitting" under the mouse cursor in Gimp?

I'm using GIMP to copy some layer out of a PSD file, But the layers are badly named, So I want to select the correct layer by clicking on the item I wanted to copy.

Which tool should I use, And please provide a screenshot.

Another problem is that sometimes you just can't click anywhere on the image since its layered.

Open Gimp preferences by going to "Edit" menu.

In "Preferences" dialog box click on "Tool Options" and enable the "set layer or path as active" option.

Close the "Preferences". Now Click on your desired object and it's layer will be selected automatically. Hare's an example!