You already have those six pack muscles. Everyone does, they are just hidden with a layer of fat. Running, swimming etc is your best bet, stay away from junk like this.
No, you don't already have these 6 pack muscles hidden by fat. There is a world of difference between a strong and a weak core and the core is really important for any other exercise you want to do.

Anyways I wouldn't bother with an ab-circle pro. You can strengthen your core without spending a fortune on a machine.
You can find lots of great workouts on youtube - this is my favourite but you can find others by doing a search. There is a part 2 as well.

Also doing hovers is great for core strength.

You also need to do some cardio to shift the fat and maybe look at the types of food you are eating - an unhealthy diet is more likely to be distributed as midsection fat.