Think too about changing the TYPE of carbs that you eat--try to avoid the "empty" carbs, or those with a particularly high glycemic index, like white bread, potatoes, regular pastas, white rice, etc.
Try to include plenty of whole grains such as 100% whole wheat bread, whole wheat pasta, brown rice, rolled oats, etc. Do a search for "glycemic index" and you'll get an idea of what to include in your diet, and what to avoid.
And start walking!