Hehe I'm not sure if you've seen the calculations required to work out which commodities are supplied/demanded. You need to use all the terrain around the city, and techs affect it, along with factors like population. Then you take away the number you first thought of. I didn't even bother even in the SP ELG.
Wildcards though depend only on map coordinates IIRC, so you might be able to work out some easy rules to help you along. However wildcards are practically only useful for helping you to decide between 2 equally attractive sites, since you don't really want to place your cities only according to wildcards. And it's still quite a messy formula.