Hey,
This will be my first time. I had a friend who gave me the number to the place he went to last year, and we called it way back in May/June and got applications sent to us. From what I know, its best to get a hold of them early. Last year I tried the same thing, but through email ,and they said everything was filled. That was back in July too. Earlier the better. There sounds like there is a bunch of different locations to work at though, so I assume some might be hiring all the time. I am not 100% sure.
Good luck.