I can lose a pound a week - but I have a high metabolism too.

Here's how I do it:
cut out ALL snacks. Drink only water (one coffee in the morning). Try to only have fruit for puddings. Have a day where you allow yourself a choc bar or a pudding too, that way if Friday is "treat day" you don't fall off the diet.
Walk everywhere. Half an hour to the shops? Walk. Five minutes in a car burns no calories. I'm not saying do a 20 mile trek each day, just walk more.
Sit-ups are your friends. You will get better results with three lots of five throughout the day than you will one lot of 20 in the morning, so go for little and often, whenever you can.
Standing burns more calories than sitting so try to get up and moving more.
Do mini-exercise - dance to the radio, run across the park, walk around as you talk on the phone.

BTW, this is for weight loss when you aren't overweight - if you are larger you may lose weight more quickly with this diet.