If you're the geeky type you might try getting an HR monitor and reading about Heart Zone training. Sally Edwards has a few books on it. Basically she gives you heart rate zones to optimize results for your fitness goals.
To simplify, she says that to lose weight you want to spend lots of time training at 60%-70% of your max heartrate which is where you burn the most stored fat. Anything more and you are burning primarily carbohydrates and stored glucose. If you do a whole workout at >70% of max you won't have burnt much stored fat and will be hungry because you depleted your glucose stores. If you replenish with fatty foods you are working against yourself.
-s