"Target toning" doesn't really work. While you can "target build" though weight training, or strengthen a particular area through weight training, you can't "target slim" by exercise.
For example, crunches alone won't give you a flat stomach. That's more due to losing fat accumulation through diet and exercise (cardio as well as weight training for large muscle groups to burn more calories) than specific ab work. Ab/core work will help strengthen the area, and working the transverse abdominals (that work like a corset to hold your internal organs in place) can help flatten a bit.
I think most people have a "trouble area" that is genetically programmed into their body. For many women, it's hips/thighs or abs or triceps (on the upper body).
I have a "pooch" that I have had all my adolescent and adult life. When I have less body fat, the pooch is smaller, but I never lose it completely. That's where MY body likes to store some extra fat. If my body fat were low enough to get rid of my pooch, I would have no breasts to speak of, and my upper body would, I think, look to skinny.