I figure you have a few options when it comes to trackings things like this.
1) you can look at the description and try to add up all the individual items
http://www.thedailyplate.com/nutriti...neric/ahi-poke
2) you can find something similar at a restaurant that does post their information (for instance pick some sushi and look that up)
or
3) do your best and count it as a rough approximation and move on (as long as you do it rarely)
For instance if I'm going out to my favorite steak house I'll get a small steak, veggies and estimate it based on what each part of the plate is. If I'm going to a party I'll divide my plate into veggies, leanest meats and a tiny bit of crachers with dip, call it 600 (or 800 depending on the dip etc) and move on with my life.

Now I make sure it's high enough I don't go back for a second plate and not so high I can't eat anything else all day. I aim for just enough that I'm careful the rest of the day.