I recommend reading this: The carb myth part 1: Why “fat-free” can still make you fat :: stumptuous.com
- it's got a lot of good tips for how to eat to lose body fat.
In short: eat more protein and more fat, and cut back on your carbs. 40f/40p/20c is a ratio a lot of people use. Eating less carbs will allow your body to begin ketosis, which basically means that you will burn fat for energy and not store the carbs you eat as more fat.
More protein is especially important if you're lifting, because it will help your body build more muscle.
Hope this helps!