That's cool.  I have gained a lot of weight (roughly 30 lbs) since I exited the Air Force in 2006.  I just recently started to lose weight because I am taking in less calories.  Finally starting to see the affects!  Been eating a harty green salad for lunch with low fat cheese and low fat vinegarette dressing, with a slim fast.  But, I pretty much say, calories in - calories out.  There is also fitday.com I believe.  Not sure if it generates a shopping list, but helps you more or less journal what you eat.