What a useless experiment. I'm a "big girl", and I'm trying to get more fit. But there is no way in hell I'm going to be able to exercise for an hour a day.

Sorry that nature in the form of human biology gets in the way of your personal politics but nature does not give a fuck about politics never has and never will no matter how much you huff and puff about it.

How much time do you devote to exercise a day? 45 minutes? 30 minutes? 15 minutes? 6 minutes? Or do you just sit around and think about doing exercise? If you are serious about getting fit you will do what is necessary to get fit. Just like if I was serious about quieting smoking I would go buy the patch today instead of another pack.

How about some research telling women - all women, not just unappealingly fat ones - what kinds of exercises benefit them and how?

Their is no one size fits all formula that will work with all women that is why you will never see research telling you there is. Lean mass vs fat mass is a bigger variable then gender is when it comes to weight loss and maintenance, and fitness levels. An overweight women needs a vastly different exercise course and diet then a thin women, weight maintenance requires different exercise and diet then weight loss or gain. I would suggest you don't use ideology if you want to be healthier.

Is it better to do just aerobics? Water aerobics? What kinds? How do exercise needs change as we age? Is bicycling just as good as step? What about treadmills? Walking on flat streets? Hills? What is REALLY the optimum heart rate - a lot of women are afraid to go to the top of their range because they won't burn any fat. I don't think that is true. How do weights fit into an exercise program? What about diet supplements? Vitamins? Water?

Have you gone to a gym and spoken with a personal trainer? They are more then willing to help you out, they will design a program based not on the needs of all women but based on the needs of your goals and starting fitness level. Most personal trainers have a college education in fitness and psychology and read and interpret the studies coming out and more important tell you how it effects you personally. This is one profession where virtually all of its members keep up on the latest studies on diet and exercise and will help guide your decisions. They are actually a better source for this information then most doctors (and no i am not a personal trainer nor in a relationship of any kind with one). If you are actually serious about getting fit this is the first thing you should do, other wise continue to use the excuse of there is just too much information out there.

But as a general rule. Don't worry about supplements when you begin. If your goal is weight loss and a generally more healthy body, train mostly with weights and build strength, lean muscle burns calories faster then fat does. Aerobics are good for general health but is not great for weight loss. Eat 5 or so smaller meals instead of 3 larger meals. If you are in it for weight loss stay away from processed carbs from you diet and cut back on total carbs for the first couple of weeks. When you do eat carbs you want to eat complex carbs that take the body longer to brake down and that keep your insulin levels in check. A half hour before and after working out you want to eat proteins. And make sure you are always hydrated. This will increase the time before fatigue sets in along with suppressing hunger panes. Don't eat 2 to 3 hours before you go to sleep. A personal training will give you an individual meal plan and work out plan.

The web gives me more nonsense than I can sort out. I want real information. I just don't know where to get it, and the media won't tell me..

The media and the web owe you nothing. If you want to find out the correct plan of action go to a doctor or personal trainer. It is not exactly advanced mathematics that they will have better answers for you. But, then you would really have to be serious and not just looking for excuses.