You might like his more straightforward books.
Misery being one of these, and Delores Claiborne. His novellas, The Body, from which the film Stand By Me was made and Rita Hayworth and the Shawshank Redemption, which was also a film without the Rita Hayworth bit of the title.
All of these are stories that don't have a supernatural side to them, they are more 'real' with human victims and villains.
The Girl Who Loved Tom Gordon is also very good, has a slight supernatural bit to it but is mostly real and quite gripping.
If you do want to go for the more supernatural side, most people love IT and The Stand and the Dark Tower series. Many of his books link into the DT series in such a way that if you haven't read it, it doesn't matter but if you have you get a kick of recognition when you find something in his other books.
I've enjoyed all the books above, Misery probably the best of them for me but Shawshank a close second. Of the others I personally love:
IT - told over a period of 30 years, about a group of children who battle a monster and grow up to discover they have to join together and fight for a second time.
The Stand - about the end of the world as we know it.
From a Buick 8 - a mysterious car impounded by a small town police force who discover it has strange, unpredictable and frightening powers.
All of the Dark Tower series - too huge to describe but covering many worlds linked to our own.
Insomnia - an elderly widower and his friends come to realise that mysterious beings are at work in their community and that some of their neighbours have fallen under an evil influence. It's a lot better than I can describe and it was one that I initially disliked and gave up on but loved when i gave it a second try. Big ties to the Dark Tower books.
The Regulators - a street is under attack from a strange group of people in a van equipped with odd weapons. It has a twin book, Desperation, with the same characters in different circumstances. You don't have to read the one to read the other, they both make sense on their own and they are not a series or books to read in order. Regulators is my favourite of the two but Desperation is good too.
Lisey's Story - A famous author's widow fends off a man determined to gain access to the author's private files, and realises that her life is in danger while discovering that her husband has left her a way to fight back. This seems to be a love it or hate it book of SK's, many people hate it but I really liked it as I think it has links to the same world as Buick 8.
Everything's Eventual - book of short stories. In fact all his books of short stories are pretty great.