Updating product price lists

Question

I'm trying to develop a numbers document that will allow me to update products in our local system when the manufacturer sends out their new pricelists.
Specifically I need a way to:
1. identify and isolate newly added products
2. identify and isolate products that have been removed
3. identify any products that have updated descriptions and or prices
Currently I can manage to do these things, but I feel like I'm going about it in a very roundabout way. Since I assume this is something that many people need to do I figured I'd ask how others are doing this. Maybe there is a tutorial for this type of spreadsheet that you can point me to.
Thank you

Answer 1

The manufacturer gives us the spreadsheet as an excel document, here's an excerpt:
And this is what I've gotten so far in my attempt to make a streamlined update process.
As you can see in addition to adding and removing new and obsolete entries I'm adding chinese translations. That is why I also need to figure out if any of the descriptions change as when they do I need to update the translation as well.
So far I've been creating a sheet and using VLOOKUP on the ItemID column for matching up the new list to the old list to see which items no longer exist; another sheet matching the old list to the new one to see which items did not exist before an another sheet to add the translations. And then I have yet another sheet that has the formatting I need when exporting a .csv document for our POS system.
I have a feeling that there is probably a more straightforward approach to accomplishing this task, that only my inexperiance with spreadsheet software is preventing me from finding.
Then there is the matter of finding changes in the descriptions and prices so I can hightlight them for the sales staff and update the translation.