I know I have wrecked my metabolism by eating too little for too long. Now my body thinks it's in starvation mode, and says "If you're going to starve me, I'm not going to burn one calorie!" So if I eat more, I just gain weight. I have researched for many years for even one program or expert who could help me lose weight due to this problem. Does anyone know of such a program that helps weight loss due to too little food? (less than 1000 calories a day).

kick start your metabolism by exercising.
Run or swim - get your heart rate going.
this will start your metabolism, then you can work on eating small meals throughout the day. You must have breakfast.
And because you have already kick started your metabolism, the extra food you are eating by having brekky and small meals throughout the day will conteract any weight gain. (hopefully!).

Have you tried speeding up your metabolism by eating little meals all day meaning at least 6 meals a day. There is a program called Fat Loss for Idiots that is online. When you view it there, there is also another diet with it that has a food group plan that allows you to eat from certain food groups at certain times throughout the day. It keeps your blood sugar level and forces your metabolism to stay active all day so you burn more calories, resulting in weight loss. It worked for me. When I tried this nothing was working. I was eating very healthy, fruit for breakfast, salads, and lean meat for dinner. I was also doing cardio 45 minutes daily. I was in a rut. Age caught up with me I guess. I had always exercised and ate healthy and all of the sudden I just started to gain weight for no reason. I was like you I guess because if I varied my eating plan for a few days by going out to eat or cooking daily then I gained 3 or so pounds in nothing flat. I tried this diet for 11 days and lost 7 pounds. It really worked and I have only gained 1 pound back. It isn't like Atkins where you shed 20 pounds in a month and go back to eating regularly and gain 15 back. Google it and good luck.