Hello Rich.
I use AmiBroker, and it has the ability to do this. I have seen some code in S&C magazine and on the AmiBroker web site. For your example, I think you can put in the indicator, and it will tell you what the price has to be in the next bar for the full stoch 21,13,5 to be 80.
It sounds like you are an Excel wiz. You could probably code it up faster in Excel than it would be for you to find it else where. It would not be automatic, but would get the job done.
Hope this helps!
Jared
jjames10@nc.rr.com
"Don't Panic!"