No matter how much exercise you do, its all about your diet. Losing weight and having abs is 90% diet, 10% exercise. If you need a free online diet plan, my wife did the The Abs Diet for 6 weeks and still uses it every once in a while since the recipes are so easy to follow. Its not really a diet, its actually more of a series of guidelines of how to eat healthy. You can also get the book The Abs Diet.
For exercise, buy: The New Rules of Lifting for Women: Lift Like a Man, Look Like a Goddess.