I went to the store and found these walnuts with 3 carbohydrates and 3 dietary fiber. That would mean 0 net carbs right? Is this a good find or is there something like hidden carbs or something i should know about?

If a label seems too good to be true, it usually is --- quite often there are errors.

One of the good things about going low carb is you get to be responsible for learning and reading -- always check such odd labels out on a carb counter, either a good paperback easily available anywhere, like the Netzer Book of Carb Counts, or an online version -- like the one available from the orange toolbar at the top of this page (and any page on this website), click on Tools and check out the walnuts for yourself.

Enjoy.