Hi Terri and welcome to the Disney Parks Moms Panel.
Mickey's Not-So-Scary Halloween Party is my absolute favourite Special Event at the Walt Disney World Resort. Although the exact dates of when it will be held in 2016 have not been announced as of yet, I can tell you that last year, the dates were released at the end of February so I would think that the 2016 dates will be announced anytime now.
I would definitely recommend that you subscribe to the
Disney Parks Blog so that you will be one of the first to know once the 2016 dates are released as this is the place where they will most likely be announced.
You can absolutely purchase tickets to Mickey's Not-So-Scary Halloween Party from here in the UK. Once they are available to purchase, you will be able to do so via the
Special Events Tickets section of the Walt Disney World website.
Wishing you a magical holiday filled with memories which will last a lifetime!
Emma