Joseph Wu's Origami Page is a great place to start, with news, articles, instructions, hundreds of links -- oh, and the galleries of Wu's own outstanding creations in categories like fantasy gaming and creatures of myth, including a section of commissioned works used in advertising and illustration, as well as several galleries of works by others.
OrigaMIT is the website of the Massachussetts Institute of Technology's Origami Club, and it includes a nice gallery of members' works. For the best of the best, check out Badass Origami at A.R.T., a collection of works from MIT's fourth annual Student Origami Competition.
There are some more nice models in Origami, another post at A.R.T.
Stones are okay, but people who live in paper houses probably shouldn't throw scissors. The Origami House is a collaborative installation that was created by a team of designers, folders, and paper engineers for the Folding Australia 2005 Convention.
Eric Joisel is a professional Parisian origami artist, and in addition to a gallery of his fantastic works, his site presents very interesting features on the creation process and a nice intro to and history on the art. His highly sculptural pieces tend to the fantastic and in addition to people and very naturalistic animals there are a number of Lord of the Rings characters, gnomes, fairies, and other magical creatures among his subjects.
Origami artist Guspath Go creates intricate and wonderful models of mostly fantastic creatures. He also photographs his own creations with a great eye.
Gilad's Origami Page is the site of prolific folder Gilad Chan, who has folded loads of models from the simple to the splendid. All the models' sources are credited and linked. But wait, there's more! In addition to his own pieces, he has also collected tons of photos of brilliant work from half a dozen origami conventions. It's all there in the huge themed galleries.
Many more artists' galleries, along with some diagrams, artist info, and books for sale are collected at the French site Design in Origami. Some highlights:
Manuel Sirgo Alvarez is an accomplished origami artist with a large gallery of beautiful works, including many wonderfully rendered insects and spiders, and a sizeable number of marine invertebrates.
Lionel Albertino specializes in insects of all descriptions, but his gallery features a few other surprises.
Sometime soon I'll do a follow up and share some good places to get started doing your own origami, with beginning instructions and nice diagrams. For now, enjoy the visual inspiration.