Do you know of any good color theory books?

Can you apply the Loomis method to animal heads?

The book Imaginative Realism also states that artists with skill and imagination have endless opportunities. I have the imagination, but I lack the skill. Of course I know through endless practice and study, along with patience, I'll develop the skills to put my imagination on paper or canvas, but sometimes I get so frustrated that I have these awesome ideas but lack the skill to bring these creations to life. Any advice on how to stay motivated and not get so discouraged?

I am currently reading the book Imaginative Realism and it mentioned that copying or studying from old masters is a great way to understand how to construct your own works of art. Of course the book has mentioned various masters who I plan to check out, but I was wondering does anyone know of any masters I could study from whose work centered around fantasy and horror? Of course I know there are many artist who do this kind of work, but to try and narrow it down, masters whose work centered around horror. Thanks.