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
Of the folks already mentioned, I really like M.C. Escher and René Magritte.