Hi there...
I am 7 months post baby and have tried everything to lose that weight, no carbs, no carbs after 7, no alcohol etc... all of which help but at my age (34) I need to exercise too. I have tried classes but you eventually plateau, you have to keep pushing yourself to avoid this... so - I can recommend personal trainers, but its expensive, however I have recently discovered a great iphone app by British Military Fitness, it's a personal trainer in your ear and having completed a few sessions with it - I can totally recommend. Obviously if you don't have an iphone/touch you can't use it.....
it's called my fitness instructor and is avialble in the apple app store (8.99 - much cheaper than a personal trainer!!!)
Good luck to all those shedding the pounds.