I stumbled upon this animation art website, Lollipop Animation.
They have a lot of great art from many different animation studios.
Personally, I find their collection of Warner Bros. art great! The pieces even have a small write-up description and explaination of the process of classic animation. Here are a few that stood out to me:
"Hand Painted Limited Edition is adapted from the famous opening used in the Bugs Bunny Road Runner Hour when the Looney Tunes led a procession across the stage. "On with the Show" was originally drawn by Warner Brothers artist Kirk Mueller and because of that, this piece has been signed by Kirk."
"This magnificent Hand-Painted Production Cel, features Foghorn Leghorn and Pete Puma, from the short 'Pullet Surprise'. This cel is hand signed by Chuck Jones and Director of 'Pullet Surprise', Darrell Van Citters. In this great short, Foghorn Leghorn catches Pete Puma trying to steal a chicken, and convinces Pete that he doesn't want THESE chickens. What he REALLY wants are all sorts of strange breeds of imaginary chickens instead, such as the Mongolian Disappearing Chicken and the Irish Wrestling Chicken. Classic Foghorn!"
"This piece is a companion to Invaders from Mars!, designed and rendered by Juan Ortiz, a piece which also spoofs the 1950s B-horror movie posters."
"HUGE close-up of our two heroes, Bugs and Daffy. Such great expressions! A truly beautiful piece of animation art taken from the animation short "The Bunny Snatchers"." (I'm going to have to disagree with their description, this shot does not happen in "The Bunny Snatchers". It actually looks like another angle from "Rabbit Fire". But it's new animation. Could it be a deleted scene from "Back in Action"? Does anyone have any idea?)
"Art directed and illustrated by Warner Bros. Artist Michael Fontanelli. Featuring 40 characters, Unsung Tunes celebrates the sidekicks and secondary characters from the Looney Tunes cartoons. Each piece is accompanied by a key sheet, which identifies the characters by name."
You can see these and much more animation art at the Lollipop Animation website!