You need to not only build up your abs but also lose the fat around your midsection, something like sub 10% bf to see them without tensing them or something like that. Just run every morning/ night, cut 500 calories from your diet a day (make you lose 1 pound of fat a week) and assult your abs with crunches, situps, V-ups, etc.

Visit http://www.iwantsixpackabs.com/abs.html for bulk information, he has a load of exercises/ videos to look at and its free.