I work as a personal trainer and can safely say that the most effective supplement that I use when on fat cutting periods is a thermogenic called Hot-Rox Extreme found here: http://www.t-nation.com/readArticle.do?id=1066793
Couple that with at least 10g of fish oil a day, and you have the foundations of an effective fat loss plan. Most "weight" loss pills around today are useless and actually can be quite harmful to your health. No one should ever use Hydroxy-cut, as post-ephedra ban has been replaced with nothing but more caffeine. I can' tell you how many failed cases I've encountered with that product. If anyone would like further info about supplements, diet, or training, feel free to PM me.