No, Marriott won't send you a welcome package. You or your closing agent should ask the current owner of your timeshare to send you the Cypress Harbour legal documents (program rules and other info) related to your timeshare.
Once Marriott recognizes you as an owner, you'll be able to set up log-in capability to the Cypress Harbour pages of
www.my-vacationclub.com . There you'll find a Cyrpress Harbour "how to use" guide, a resort calendar and other useful information.
You should also review all of the FAQs for this BBS Marriott forum. They are located at the top of the list of topics for the forum.