Move pictures slightly in photoshop elements?

'joiners', where you join lots of pictures of one scene together to make an overall picture of the same scene. The trouble i'm having is aligning the photos. Is there anyway to move pictures in photoshop but only minimally? i've been trying to move them with the mouse, but it is moving them too far. Is it possible to move the picture and type in the amount you want to move a picture or how far you want the picture to be from the edge of the page?