Having grown up in an "art" town and having had it thrust upon me from a very young age, it took me a while to come to give paint and canvas its due, and it actually came to me by working in a book store as a teenager, a busy one, where I really couldn't read any good fiction with customers coming up one after another, so I flipped through art books. Some painters I like, with some quick examples picked from la Google.
Caspar David Friedrich
Edwin Austin Abbey
Don Van Vliet a.k.a Captain Beefheart
Enzo Cucchi
Salvador Dali
Aaron Douglas
H.R. Giger
Hokusai
Philip Straub
Andy Kehoe
Of the folks already mentioned, I really like M.C. Escher and René Magritte.