There are many ways to make animations of your own, aniBoom is a site that allows you to create animations using their free animation software. The site also lets you upload your animations and watch them, as you would on YouTube.
Game sprites are basically picture used in 2D games or animations you put 1 picture then next and then next and the character well move you need an programme to make the animations i use windows movie maker and to make a game game maker go and try it
Disney animations can not be legally purchased by any singular person. Animations created by Disney are the sole property of Disney. However, if someone would find Disney animations intriguing they could always join the animation team.