I haven't read all the replies, but from what I have, you've got some great advice already.
I eat pretty low carb/fat and high protein. I almost never eat potatoes pasta or rice, and when I do, it's a very small serving of brown rice and whole wheat pasta. Some of my favorite low carb/low fat foods:
Cottage cheese. I put some in a bowl with blueberries.
Tuna. Mix with just a tiny bit of low-fat mayo or ranch dressing and make an open face sandwich with just one slice of whole wheat bread. Melting a single slice of cheese on top is tasty, though it adds some fat.
Egg whites. After getting past the food wasting aspect of it, I make egg white omeletes or add just hard boiled egg whites to a salad. Pure protein. Sometimes I'll do one whole egg plus a couple of whites for my omelete. Tastes better, but still less fat than using 2 or 3 whole eggs.
Lean meat. I love thin sliced turkey and chicken. Lots of packaged deli meats have tons of sodium, so I buy organic and I have a few slices for a snack, or on an open faced sandwich.
String Cheese (especially low-fat versions). Another good snack. If you peel them they take a long time to eat, too, so it feels like you're eating more.
Laughing Cow light cheese wedges. Love these instead of butter on toast. Oh, and on the bread, read labels before you buy. You want "100% whole wheat" bread. If it just says "made with whole wheat", it's only partially whole wheat. Even among the whole wheats, bread varies a lot by size of slice and nutrition content. The brand I buy has 13g carb, 3g protein, 1g fat and 70 calories a slice. Some brands can have over 20g carbs and 110 calories a slice. Not THAT much if you only eat a slice or two a day, but it adds up and every little bit counts, IMO. There are also some brands that make "light" breads about 40 calories a slice, but IME these are very small slices, and I'd need to eat two of them so why bother? Try some different brands and see what fills you up enough and tastes good to you.
Remember that veggies vary in carb/calorie content, too. Peas and carrots on the higher side. Green beans, broccoli, zuchini, cauliflower on the lower side. Now, carrots are very healthy for you, so don't avoid them completely, but don't make them your only veggie, either. I love to eat raw zuchini sticks as a snack, or cooked and sprinkled with a tiny bit of parmesan.
Get a kitchen scale, too. It's so easy to keep track of serving sizes with one. Just put your plate on the scale and weigh each food as you dish it out. It eliminates a step and avoids dirtying the measuring cups/spoons. I especially love using it for salad dressing, which is so easy to over-serve.
Writing down everything you eat makes it harder to cheat on a diet, too. There have been times when I'm dieting that I find myself eyeing my kids' cookies or candy, and if I didn't have to write it down, I might have had some. Somehow, writing it down makes it more real. Because even though it's not true, don't we all have that feeling that if no one sees us eat the snickers bar, and we eat it really fast, then it won't have any calories?

I agree with the person who said not to deny yourself too much, though, or the cravings will just intensify. But I know myself and if I eat one M&M, I"m going to eat the whole bag.

I keep sugar free fudgsicles in the freezer (40 calories each) for my chocolate cravings and that's good enough for me.
Also, the first week is the hardest, but remember that it takes 3 weeks to break a habit. Once you have eaten more healthfully for three weeks, it will become your new habit.
Oh, and don't forget to exercise! Walking is a great start. Also, lift small weights and slowly work up to heavier ones.
Good luck!