The previous suggestions are great. I would add that a diet "study", where you keep track of LITERALLY everything you put in your mouth for several days to a week, is really, really helpful. You 'forget' the little things you eat during the day that in and of themselves aren't much, but when put together can really add up. Of course if you could afford it, working with a registered dietician would be optimal. For my patients that are really set on loosing weight but can't go the dietician route, I strongly recommend "The Abs Diet" originally published by Men's Health magazine (yes they now have an "Abs Diet for Women" too, but the science is the same.) It is based on good science and really isn't a diet in the classic sense. It's really a way to make the appropriate lifestyle changes to get the weight off and keep it off because you don't go back to eating and exercising how you are now. That MUST change or you get the yo-yo dieting effect.
Something that I just started reading about (it's been all over the popular press, and has been spotlighted on Dr. Oz) is coleus froskohli supplements (active ingredient = forskolin.) Some of the literature is equivocal, but most seems to indicate that men and women who added c. forskohli (yep, the houseplant known as coleus) to their diet lost an average of 1 -3 lbs/week. It seems to promote loss of fat while maintaining muscle (which burns more calories metabolically anyway, so that's a good thing for several reasons). It is NOT a stimulant, but one side effect is that it lowers blood pressure, so caution should be exercised if you are already on BP meds. The theory is that lean body mass is promoted partly by increasing free testosterone. Uh-oh, that sounds bad, right? But that's not the only thing it apparently affects.
Other research which was looking at triggering the gene for aromatase and overall aromatase activity, uses c. forskohli in test subjects to stimulate aromatase activity (check out this
scholar.google.com search:
http://scholar.google.com/scholar?q=aromatase+%2B+forskolin&hl=en&btnG=Search&as_sdt=1%2C39&as_sdtp=on). Aromatase is the enzyme, in men and women, that converts testosterone to estradiol! So even if free testosterone (DHT is really the bad-ass responsible for masculine characteristics anyway, not T) is increased, if the gene for aromatase is up-regulated, more of that T will be metabolized to E. Less T will be converted to DHT which is good. Increased natural E is also good! Now, the question in my mind is: are increased free T levels completely offset by up-regulated aromatase activity? Not sure on that one, but c. forskohli supplements seem promising to help with weight loss.
Hope that helps.