Gris Grimly is the author and illustrator of children’s books like Jordan Ray’s Muddy Spud and the Wicked Nursery Rhymes series. He is also the illustrator for numerous other books, including The Dangerous Alphabet with Neil Gaiman.
His web site, Mad Creator Productions, has a showcase of many of them, as well as a portfolio of art that includes both color and black and white illustration and gallery art. (I can’t give you direct links because the site is in Flash.)
He works in ink and watercolor, often using fine lines drawn with technical pens over which he lays washes, splotches and glorious spatters of watercolor. He also appears to use ink spatters, giving his gothic horror themed illustrations a wonderful feeling of looseness and texture.