In my experience, if you want a freebie Myfitnesspal is as good as you are likely to find. It covers carbs for most foods, its shortfall is that anyone can post nutrition information, which will only focus on what the poster is interested in. If you are prepared to pay Carbs and Cals offer one, it is about to be updated but if you buy the current version the update will be free. they also produce a book of the same name.