I am in the same boat as you, except my daughter's 6 1/2 months. Over the past two months, I've been able to lose 14lbs and 5% body fat by excercising 5 days a week an hour at a time. Mix up your elliptical workouts with some resistance training. I know it sounds crazy to lift weights when you want to lose weight, but it really does make weight loss easier. If you don't have weights and can't join a gym, try doing planks, push-ups, dips, burpies, mountain climbers, squats and lunges. Those can all be done without weights. When you do any cardio you should keep your heart rate in the 60% zone, that way you burn fat.
As far as snacks: yogurt, nutrigrain bars, granola bars, hummus, almonds, pistachios, walnuts and dried cranberries, peanut butter, low-fat string cheese and fruit have worked the best for me. I totally agree with everyone else that says if it's not in the house you won't eat it. Before I started really watching what I ate, we had all sorts of junk in the house. I kept a food diary for a week and was shocked at all the junk I ate through out the day just because I was home.
It's a slow process losing weight while breastfeeding. I've done hours of research on the subject. And I learned that 2 lbs a week is the absolute most you should lose. You should never feel hungry while breastfeeding. Try to get on a schedule of eating a small meal (around 300 calories) 6 times a day. Drink tons and tons of water. This way your supply is maintained and you're not starving. Also, if you eat small meals through out the day, you won't be as likely to eat a giant meal at dinner.
Most important - keep on moving. You can do it!