For Ladder Divisions do they announce the ladder ahead of time?
Depends on the contest.
Most of them use the standard AYYA (or whatever it’s called now - National Yo-Yo League?) ladder routines. You should be able to track down the current rendition here:
p.s. - I changed thew title of your post to be more descriptive.
To answer the question at hand. Yes, I have never heard of a surprise set of tricks. Being a fairly consistent competitor in intermediate trick ladder (pick your trick) I wish they would do an extension or mild update to the list. Either way super fun and prepares you for the nerves of being on stage and such.