Where to buy:
Almost all of the costumes in the movie were custom-made, so you can't purchase an identical outfit like Alice's/Hatter's/Duchess's/whoever. You'll have to make it or alter it yourself.
+ Alice's shoes are
John Fluevog Inge in
plum. They're not currently producing them, but are re-releasing the plum color for Fall 2010, due to the popularity of the shoe from the mini. (It is also possible to find a more cost-efficient pair of boots on a site like Amazon and then use leather paint to make them purple)
+ Alice's tights are probably the easiest to find out of any of her costume. I purchased a pair of Hue tights (in Sienna, a brick red color) from Macy's, and a pair of Banana Republic tights (in Burgundy). Either would be acceptable, considering that in some shots her tights look more orange-red and in others they look more pink-red. Hue tights are super comfortable and come in, quite literally, every color you could imagine.
Fabrics:
+ Your mods are currently studying all the fabric websites to find something close-to-exact. On the Hatter front, nothing has been found yet. On the Alice front, any sky blue (with faint diamond print) cotton would probably work. Considering the work of the costume designer, I imagine the fabric was probably custom-printed as well.
Spoonflower would work if you'd like to design and print your own fabric for the costumes.
For Alice's coat:
Option 1 For Alice's dress:
Option 1 For Hatter's shirt:
Option 1 (Not exact by any means, but the closest I've found.)
Patterns:
+ For Alice's coat,
Option 1,
Option 2,
Option 3. (I've personally used the first one, and it'll give the right shape, but it'd definitely require some modification.)
+ For Alice's dress,
Option 1,
Option 2,
Option 3 Mod note: This entry will be continually updated with our research (and the research of the comm members) when new info is pointed out.
Also, a lot of my research is Hatter and Alice focused, so if you know of stuff that would work for other characters (Duchess, Jack, 10 of Clubs, etc), point that out, too!