I just caught an episode of Pawn Stars — a relatively new episode, I think. It's called "I'll Be Doggone."
In it, a lady brought in a copy of the 1958 Peanuts paperback called Snoopy, containing what was purported to be an original sketch of Lucy by Charles Schulz. Chumlee, of the pawn shop's staff, called in an expert to verify that the sketch and signature were legit. The expert came in, said they were…and Chumlee bought the book from the seller for $1400. Presumably, if this was a legit transaction and not just one staged for the cameras, the book then went on sale in the shop for well over that amount.
Now, I'm always hesitant to say a drawing is real or fake unless I hold the actual drawing in my hands. So I won't go any farther than to say that on my set, it sure looked phony.