The whole trick to awesome abs is yes unfortunately it is the diet which is the most difficult part. You want to slim out and keep your fat intake to a minimum.
Then you want to work an ab machine with good blasts on the most weight you can do for 5-8 reps 5 sets or so to make them stick out. Each week.
The guy who runs the gym I go to is retardedly cut up, and has a 6 pack. And is 100% natural. But he is obsessive with his diet and about the worst thing he puts into his body is coffee.
It comes down to how bad do you want it.