It's difficult to comment as I haven't seen the original, but let me throw it back at you. Why did you copy this particular piece and what were you looking to learn from it?
Here's a link I'm posting to some PDF copies of Andrew Loomis' art books that you should find very useful:
www.hightail.com/download/OGhk…Andrew Loomis died in the late 1950's so he won't be upset you're downloading his books. His art is very classical illustration that I think will serve as a good basis for where you want to go later.
As far as other artists work to look at I'd recommend looking for yourself and making your own mind up. For a start you can look through the artists I follow on my page and pick for yourself. They're all very different and have very different styles.
When thinking about the supernatural and horror a lot of it is about pacing, storytelling and lighting. Experiment in drawing objects and people lit to give a strong contrast.
Yours,
- Dave