In most of the low carb vegetables I don't think you have to be too exact. I do use standard cup measurements when I'm putting my portion on my plate.

I use fitday.com to figure out carbs for things that don't fit well in measuring cups, like brocolli. Fitday will give you about four ways to figure the carbs in brocolli; cups, florets, spears, etc.

That's still kind of cumbersome, but you could always weigh the results and figure the carbs per ounce that way for almost any kind of odd shaped food.

slowday