I'm dressing up as Alice for a Twilight-themed party on halloween, so I looked up some pics on the internet. I also asked a few questions about it so you could check it out.
Now, for the make up you could check out AllThatGlitters21 and VampWhoDoesntSparkle on YouTube.
I also know of a great foundation which lovely Jenny told me about here, on Yahoo.
You can find it here:
You could also purchase it at Blue Banana.
Clothes? Just try something dressy. Alice loves ruffled dresses and loaaads of layers. I'm going for the look when Bella meets her at the Cullens house. I guess it's the easiest to make and most memorable.
You could buy the dress at Diane Von Furstenberg's site (it's called the Oleada dress), except that it's for 400$ and it's out of stock. There is also a cheaper one at Wet Seal, but it's currently out of stock too. I bought a similar dress at Esprit, anyway.
I bought the cardigan on Ebay - it was really cheap. I had problems with finding the choker - people told me to get it from Claire's, but I couldn't find it. You can buy it at Target. I looked it up on Ebay and some are soo cheap. I decided to make one myself, though.
Oh, and remember: Alice ALWAYS wears ballet flats, no matter what...
Hope I helped. And have a great halloween party.