Thanks to a heads up from Chongweikk, I found this thread at CrimsonDaggers in which artists were given the challenge of creating re-imagined art for nine of Hayao Miyazaki's nine canon films. This means art for films including Nausicaa of the Valley of the Wind, Castle in the Sky, My Neighbor Totoro, Kiki's Delivery Service, Porco Rosso, Princess Mononoke, Spirited Away, Howl's Moving Castle and Ponyo.
I have added ten select posters from the lot in the gallery accompanying this article and labeled each. The poster created by Zaphk for My Neighbor Totoro is probably my favorite of the lot, but there are some excellent pieces of art here.
Links to some of the artists can be found directly below.