I gained 50 lbs in nursing school (doh!)
I lost 30 lbs last year doing weight watchers...got tired of thinking about "points," so I slacked off for awhile. Have maintained that weight loss, and I'm now learning how to follow a diabetic diet.
I'm not diabetic (though my mom and her father are), but it's a great way to lose weight, and it's healthy.
Some good websites:
American Dietetic Association:
www.eatright.org
American Diabetic Association:
www.diabetes.org
lots of recipes (of all kinds, not just healthy)
www.allrecipes.com
You need to have a certain amount of fat in your diet, or you will be hungry all the time. Also, a lot of low-fat and fat-free foods are higher or just as high in calories, sodium, and sugar as regular food.
I think I might set up an appointment for myself with a R.D. sometime soon...I'm trying to get away from the frozen, packaged, and canned stuff, but I don't have a lot of experience with healthy *cooking.*
Drink a lot of water...
Identify why you eat, besides hunger. (I happen to have a talent for eating when tired, stressed, angry, upset, happy, and bored, haha)

Have a plan for dealing with those things besides eating.
A trainer told me that successful weight loss is a triangle of: good nutrition, cardio, and weight training - if any of these are missing, you will not have optimal results.
And keep in mind that it only takes cutting and/or burning 500 calories per day to lose 1 lb per week.
PS...do not, under any circumstances, leave a salad unattended...