Lovecraft's writing, from 1917 to 1937, is on the boundary between fantasy and horror. It's a peculiarly intellectual kind of horror, for the most part -- the horror of people who learn that the universe in which they live is far less sane than they thought. Lovecraft's world is one that doesn't know that it's under siege, that utterly alien beings are just a reality away -- sometimes inimical, sometimes indifferent but still capable of being misguidedly invited in. It's a world where people who seek out forbidden knowledge are broken by it, not because it's evil or corruptive, but because it was never meant for human beings. This is horror in the older tradition, in which we are less likely to be see people being turned into snacks than to hear the story from the person who found the bones.
Most of Lovecraft's work -- short stories, mostly -- is still in print. The stories generally stand alone, although many of them share plot elementsand backgrounds. The common elements and backgrounds for much of his work are known collectively as the Cthulhu mythos. The name is misleading -- Cthulhu is the subject of just one of his stories, neither the best of his stories nor the most impressive of his subjects -- but it has stuck, and we're pretty much stuck with it. It's not entirely inappropriate, as the story is one of the horrific and unknown impinging almost unnoticed upon our world.
Lovecraft is another author whose writing you owe it to yourself to try. You may not care for it -- some do, some don't -- but you won't know unless you try. You can't judge on the basis of other, similar, authors, because there *are* no similar authors, though there are many authors whose work reflects his influence. (That said, a word of warning is in place: There are a good number of books on the shelves that say "Lovecraft" in large print, but acknowledge themselves -- in finer print -- to have been 'completed' or 'coauthored' after his death, most often by August Derleth. They are inferior pastiches.)
The stories (***). Collections of Lovecraft's stories are readily available, new or used, in paperback. Stories such as "The Dunwich Horror", in which a mad bargain with a creature from Beyond becomes, decades later, a matter of very public concern. This story was made into a weak movie which, among things, misdelivered the punchline. Stories such as "Pickman's Model", a story more cute than horrific, about an artist who paints unreasonably realistic-looking monsters. Or such as the eponymous "The Call of Cthulhu". Lovecraft's earlier stories contain many of the same plot elements, but are closer to fantasy. They are meant to evoke wonder, rather than horror. The best of these may be "The Dream Quest of Unknown Kadath".
Lovecraft was mainly a short-story writer. He left some poetry which is of limited interest to those who are not devoted Lovecraftians. And he left two short novels. "At the Mountains of Madness" (**+) is a longer Cthulhoid taleabout an expedition which goes looking for the unknown -- and is far more successful than it would wish. "The Case of Charles Dexter Ward" (**) is horror -- about a man who discovers the secret of necromancy and uses it badly -- but it's not related to the bulk of his work.
Dani Zweig email@example.com
You've read the book. You've seen the movie. Now eat the stew!