The only thing that helped me not be hungry was to follow Dr. Mirkin's advice.
drmirkin.com
This is all free info. Don't buy the book. He doesn't sell them. Everything you need is on his web page and if you see someone selling a book of his, they probably got it free and are trying to make a buck.
Whole grains is what keeps me full. One main thing is to understand what whole grains are. All those breads, cereals, crackers and pastas that say they are whole grains are lying. As long as the whole grain is ground up, the body still considers them as sugar and you will feel hungry after eating them. To stay full, stick with steel-cut oatmeal and eat the actual whole grain such as barley, wild rice, etc.
Many stores now carry them frozen or packaged and you can just pop them in the microwave. Trader Joe's for example, has single serving frozen steel-cut oatmeal for a reasonable price. I can't remember if it was less than a dollar or just a little more per serving. It comes in servings of 2. That itself will give you a great start for the day. It is even sweetened gently so it's palatable.
Beans are also a great way to fill up. Take Beano if you have to. It really helps with gas issues. Whole grains plus beans compliment each other nutritionally. Dr Mirkin's website has a bunch of free recipes. I usually make a big batch and freeze them. Even my 3 yr old loves the dishes. It's not diet food. It's real, good, healthy food.
Fruits and veggies are great but I don't fill up on them alone. They are more like snacks for me.
Diet sodas can also make you feel hungry. Even things like Crystal Light, etc. Or anything with artificial sugar (light yogurts, ice creams, etc). The artificial sugar makes your body think it's getting sugar and when it doesn't, it craves the amount you "cheated" it. So avoid anything "diet" or "sugarfree" if it has artificial sweeteners.
Hope this helps.