The ones I can recall are next to the north pool by the Palms, about the middle of the rooms between the old & new sections ( east of the main sidewalk), the fitness center across the street north of the pool, and I'm pretty sure there was one near the swim up bar pool. Those are the ones I remember but I'm sure someone will post if I missed any.
I have never seen the one by the Palms open. Last year there was a sign by it in April and Oct saying it was closed for cleaning or maintenance or something. I can only think of the ones rjammin mentioned but there are actually two by the swim up bar, one on each side.