Crunches only tone the abs. Most likely there will be some fat tissue in the way of the abs. Therefore, you must lose this so that the abs are more visible. The best way to do this is with cardio exercises such as brisk walking, swimming laps, jogging, biking, running, cross-country skiing, etc. You need to do all these exercises in a cardio way (otherwise you can be wasting your time)
Jump roping, mountain climber, a plank exercise when you quickly alternate touching your chest with your knees, and many more are okay. When you've lost all the flab, you can start doing crunches, curl ups and sit ups.
Sit ups and anything that uses upper body strength
Situps and crunches are good abs exercises.
Well, you already have abs. If you didn't, your guts would fall out. To develop your abs, eat protein and exercise them.
Yes, there are many exercises that can be done with exercise balls that will incorperate the use of your abs. Most balls will come with a workout sheet explaning some of the exercises for you.
You can work out your abs every day, if you vary the exercises that you use. If you want to only do abs once or twice a week, you should do a number of different exercises on those days.
In addition to a proper diet and exercise circle abs will help you to tone your mid sections. I have also found pilates exercises with bands to be very helpful.
The Yukon AB Crunch Machine has mutiple exercises that it can preform to work many different areas of your abs. It is considered to be the best for range of exercises.
There are many exercises for conditioning the abs. Some of these are the basic crunch, the plank, the bicycle, the abdominal hold, the side crunch, and the hundred.
This is a great site for ab workouts. There are various exercises which means you can pick what suits you best. http://exercise.about.com/od/abs/ss/abexercises.htm
Any exercise that involves the abdominal muscles or abs will be effective with continued use. Some exercises for abdominal muscles are squats, crunches, the side crunch. There are also exercise equipment made specifically for the abs.
Not to any extent, the best exercises to target the Abdominal Wall Muscles, involve bending, ie Sit-ups etc.
Some exercises that will tone exercises are crunches and yoga exercises. The lung may be a good thing to try. Push ups will help make the area tighter.
The best thing to trim down and get abs, is actually simple. Less junk food, eat more organic food, and more core exercises. Sit ups is a great way to get sexy looking abs. Good luck!