What a great thread! I have a bunch of WDW-related designs for t-shirts, mugs, stickers, etc. at:

• TeePublic, teepublic.com/user/seescotty <-- Most well organized, check out the "Mouse-oriented theme park" album
• Redbubble, www.redbubble.com/people/SeeScotty <-- Not the most well organized, but I sell a lot of stickers there
• Amazon (Prime eligible!), amazon.com ... SeeScotty <-- Not organized at all, so WDW is mixed in with everything else, and they're super skittish about copyright infringement (so their algorithms imagine it exists when it doesn't), so not as many WDW options there, but it does have my favorite--a fantasy monorail system t-shirt, which TeePublic yanked.