There should have been a packet with an acceptance/declination of offer form, a stapled together packet of information about the Luskin School, and your admissions decision.
My acceptance letter also said that they would be sending more information by March 31st with more details.
I submitted it on the day of the deadline and was notified via email on Valentine's Day. I received an official letter about a week and a half after that.
I'm hoping to be able to visit in a week or two, but airfare is sooooooo ridiculously expensive.
I was accepted about a month ago, but have not received information re: financial aid/fellowships. They said that information would come in the mail in about a week.