Making sure you aren't overtraining is essential. Your delts are a relatively small muscle group, and get hit hard in both your chest and back workout. If they aren't growing, I suggest working them with one of these bodyparts (or in less volume on both days). When I started training this way, my delts got much fuller.
As for excercises, I think wide-grip upright rows are absolutely essential. For me, they are the best exercise for targeting side delts. Side raises, front raises (if you think they're really necessary). All sorts of presses, but I prefer to use mainly dumbells, as they are easier on your shoulders. Shoulders are easy to injure, and that can keep you out of the game for a long time.