I don't only like cover artists. I like good book illustrators. One pair of names I remember from childhood is Beth and Joe Krush. They illustrated the six Borrowers books, of which I still have the first four in a boxed set. They illustrated two of my very favorite book series.
Illustration from The Borrowers, by Beth and Joe Krush
The Borrowers has been adapted for film and television several times, most recently as the anime The Secret World of Arrietty, which has received good reviews. One strange adaptation starred John Goodman, along with Hugh Laurie (before he got famous) and the actor who played Arthur Weasley in the Harry Potter movies, alongside the Draco Malfoy actor from the same series..... both of them dealing with a character who happened to have the surname Potter. This version is the one most of you might know the best, as it was marketed and distributed extensively.