Leading up to the Expo, Kairi-Moon will be selling Secret Colours, an art book with step-by-step guides as to how they were made. The quality of work in their looks amazing to be honest, there are a couple of previews on the Sweatdrop community forums here.
One section of the book will be a general sketchbook-type section, where everyone of a wider range of abilities was asked to submit a random doodle (this was my point of entry ^^ ). Mine's here which is basically a random sketch that I got carried away with. I'm looking forward to seeing how it looks in print alongside everybody elses! ^^
Be on the look out for it at the Expo - I think there are a lot of different artists within those pages, so it will be a good chance to see everyone's work. Yay!