Cosplaying Help is needed dearly!?

I want to cosplay as Rue from Princess Tutu. I don't need the wig since My hair is already black and I can easily put my hair in a bun and make curls using gel. I know already know where I am buying the Red Tutu but, I don't know where I can buy red ballet shoes. Please be specific! Yes, I can buy online but I've looked over 20 pages on Google.