There seems to be A LOT of companies releasing artist edition laptop skins - which means your choices of artists is expanding!
The selection over at Infectious is pretty great - Mijn Schatje, Buff Monster, Shag, Zeptonn, Dalek, Junko Mizuno, Jon Burgerman and others.
Nook Art's selction includes Misery, Elana Mullaly, Jon Burgerman, and Tama. You'll have to pay for shipping from Australia to get stuff from Nook though.
I can't speak for the quality of the skins at Infectious and Nook Art, but I bought a Catalina Estrada Mac laptop skin from Gelaskins for a friend and it was gorgeous. Super easy to apply and looked beautiful on her laptop.