good link!
I've been on a major weight loss effort lately. Have been using an app called "my fitness pal", by Under Armor. I've found it very helpful in understanding my calorie and nutrient intake.
It has an amazing database of this kind of stuff. I've not found much that it doesn't have yet.... scan products by barcode for packaged stuff. For restaurants you can do a keyword search...."Burger King Whopper Jr." for example....it's very thorough. Occasionally for more odd places, or mom and pop things, I'm still able to find similar items.... such as "egg roll" from my local chinese takeout joint.... well in the database I can find lots of options for eggroll and pick one that's probably close enough, such as one form ameriserve, or one from Scwann's, or one from Pagoda, etc...
The app seems to be crowd sourced, but I wonder if it's not pulling data from the same source as your linked site....regardless, I'm going to try to remember it as a backup reference!