Is this a store where you can just walk in and pick out a wand or is it an "attraction" that you can only get into at certain times of the day? Thanks in advance.
You can get all wands at the Owl Post, and character wands at the Universal store in Citywalk and at the front of IOA. There are also an outdoor cart in front of Hogwarts that sells character wands. The birthday wands are only at Owl Post.
Ollivander's itself is just a little show that runs continuously during the day. The show empties into the Owl Post.
there was a huge line for this store when we were there last Thursday. It was outside, it was long, and it didn't seem to ever go away. Some of our friends got wands - but bought them at the merchandise store at the front of the park on our way out.