Hi and welcome. I do suggest you read the Atkins book, or at least visit the Atkins center
www.atkinscenter.com and see the list of induction foods. Induction is a two week kickstart to weight loss consisting of proteins, fats, and 20 carbs from mostly vegetables.
I personally don't recommend any bars or fake foods, they effect some people by making them stall or gain weight and making them crave real sugar, which should be avoided.
Atkins has 4 phases, induction, on-going weight loss, pre-maintenance, and maintenance.
If a food has fiber, the fiber is indigestable and can be subtracted from the total carb count...however, some manufacturers are presubtracting the fiber for you, making the count look much lower. You can use
www.fitday.com to find out exact counts of carbs, calories, fats, proteins etc. and it's free.
Hope this helps,
Beth