No offense but odds are if you are overweight, you don't need a mail-order diet. You need a life style change. After all of the things I have learned about nutrition and the way the human body uses and requires food and the way even something like Nutri Systems is designed, eat smaller meals more frequently and you will begin to lose weight. If you eat 3 meals a day that are 700-1000 cal each, make that 6 meals or more consisting of 200-300 calories. Even if you don't eat any less than before over the course of a day, you will lose weight because of the way the human body metabolizes food.
Use common sense eating habits too. A serving of meat is actually supposed to be no larger than a deck of cards, not big enough to cover a 12" diameter plate. Now I know that not eating a piece of meat large enough to kill a man isn't very manly but neither is being horribly out of shape.