iCal and countdowns

Hi,

I would like to add a series of events in an iCal calendar with the number
of missing days to a certain event (i.e., for each day an event with
something like "N days to ...".

I tried to see if there was some automator script to allow me to do it in
one step (inserting all the entries manually is not really an option) but I
didn't find anything ...

Many thanks for any hint!

Matteo