I'm not sure about the spreadsheet, but one thing to help budget for us was picking out all our meals.
We looked at every menu where we had Adr's, or if we thought we would be in the area for quick service, and actually chose what we might want to eat. We added all the prices, figured for tip, and bam, estimated cost of dinner/lunch whatever.
It seems tedious but it was actually a pretty fun evening looking over all the food menus. We generally rounded up, added a few bucks here and there, and honestly we don't HAVE to stick to what we picked out. We didn't actually record what we decided, just generally picked out something we might want to eat.
Now here is where it gets really dorky. On our first trip we saved all our receipts for the day, then added them up back at the hotel at night to see if we hit our mark. It was kind of fun because we didn't take it too seriously. If we went over, fine, no big deal. If we were under, sweet! More for the next day.