Find a physical activity that you like or can learn and get thoroughly involved, boxing, kickboxing, martial arts, all star cheerleading, learning to swim, tennis, raquetball, skating etc.. Make a work out schedule and stick to it. Try to get cardio & muscle training in it, so whatever weight you lose you don't gain right back because you've changed your metabolism.
Try dietmaxx.com and see if these pills work for you. Take them for a week and see if you notice any difference. What works for some in the pill world might not work for others but this is supposed to really curb the appetite.
Try to eat 4-6 mini meals everyday including a lot of fiber and drink a ton of water. Less refined sugars and starches, stick with good protiens beans/nuts/fish/chicken/turkey/tofu/soy etc.. and lots of fresh fruit and veggies for your meals and snacks. What types of food do you usually like to eat?
Most of all stay busy, stick to your schedule and find motivation anyway you can. Plan activities around how physically active they make you. Go skating on the weekends or bowling or to the batting cages or out dancing at a club... Join some adult sports team so you have to stick with what your doing.