Renato Alarcão [flash] is a Brazillian children's book illustrator with brilliant sketchbooks. [More Inside]
Visual Thinking: Sketchbooks from the Archives of American Art: Hundreds of sketchbooks in the Archives of American Art form a vast repository of ideas, perceptions, inspirational imagery, and graphic experiments. As personal records they afford an intimate glimpse of an artist's visual thinking and reveal aspects of their creative process.
Finally,a home for the Turner bequest : In 1856, nearly five years after Turner's death, his estate was settled by a decree in which the works found in his studio that were considered to be by his own hand were accepted by the nation as the 'Turner Bequest'. This comprises nearly 300 oil paintings and around 30,000 sketches and watercolours (including 300 sketchbooks). All of this work is now available to view online at the Tate. If nothing else you can get some beautiful wallpaper for your desktop.