There are indeed some supplements that can aid you with fat loss, but in the end of the day everything will boil down to two basic things - diet and exercise. No matter what supplements you will be taking, without those two components you will not get any results. Even with such potent compounds as steroids you will not get to lose fat unless you follow a good diet and train regularly.
Personally, I have not tried the green coffee, so I can not judge on it. I did try n2Slin, and it is very good for carb redistribution, and to make them go into the muscles instead of fat, but yet again - this will be useless if you do not move and eat junk food.