Definitely routine sets of situps every day, you will see a difference. Also ab sits (hard to explain) in the shape of a V work wonders, and there are different variations ( chopping lets up and down, making a scissor-like motion, circles, etc). I think stack.com might have some good workouts as well. My high school coach uses it for all kinds of things.
Have you tried the little jack vorkout ? http://www.youtube.com/watch?v=TKCGe2Ezr��
Start Jogging! it s the best fat burner
.