Originally Posted by znak
If you goal is to have a six pack, you need to fix your diet. PERIOD. You could have the strongest abs in the world but if they are covered with a layer of fat, you will not see them.
If you goal is to have a strong stomach, work out. Do the exercises recommended above or even the ones in the workout you are doing. (I mix it up almost every workout, but that is my approach... the key is attack!)
You have to push yourself. If you can do 45 today, do 47 next time you work out. If you can do 10 hanging crunches today, do 12 next time. Takes time, but you will get stronger if you push yourself.
Also, squat and deads do a lot to your core strength, so careful if you are squatting a lot and doing major abs workouts, you could end up kind of boxy...