Walt Disney World park tickets are available in many locations. You can buy them from your local Disney store, online via the WDW website
HERE, over the phone from Disney at 407-W-DISNEY, via an independent ticket seller such as undercovertourist.com, at your DVC hotel upon arrival at WDW, or at the park ticket windows and guest relations offices. How to purchase the ticket is really up to you.
As a starting point, you may want to go to the wonderful independent website allears.net. Search there for two articles:
- "WDW Ticket FAQ". Describes what all the different types of park admission tickets are.
- "Ticket Price Comparison". Shows which are the most cost effective ways to purchase park tickets.
Good luck with your planning.