I have already posted twice, but I just read your last message. I don't want you to get discouraged. I am an exercise physiologist with a minor in nutrition. I have worked with over 1000 people. I have seen people lose on all types of diets. By far the greatest success, long term, that people have had is with a balanced diet that contains moderate amounts of good protein (even from animal sources), good carbs (low glycemic), and good fats. Of course calories are important also. You don't want to lose weight fast for 2 reasons. 1) You can develop gall stones (fat and cholesterol are processed in the liver. When there is stagnant cholesterol in the liver, it can start to solidify). 2)Your body's levels of leptin(a hormone that has a MAJOR roll in weight loss) lowers making weight loss increasingly hard. This phenomenon is largly responsible for plateaus.
The best thing to do is figure out what calorie level you maintain at and go SLIGHTLY below that. Once a week or so, go slightly above your maintanence level. This will help stabilize leptin levels (it also helps you get through the weekends). You can further increase caloric expenditure with exercise. Strength training will increase your metabolism significantly. Cardio should be used primarly to strengthen the heart, but can also aid in weight loss.
The reason I am so against Atkins (besides all the research) is from my experiences with my clients. Every single one of them, who tried it, had problems. Often they would be dizzy. Some would pass out after a workout. Some had GI problems. Many had problems concentrating, and a host of other maladies. Most of them followed the program to the letter. Atkins himself often passed out at lectures. I know people who went. Happily, all of my clients eventually stopped Atkins and were succesful using the moderation approach I outlined above.