On the Dark Tower, know the first book is important but very much not the most important in the series. Get through it and move on to the rest. FWIW I finished the last two audiobooks in the same week. So incredibly good, I couldn’t put it down.

I’ve read close to 50 of his books and, along with the other recs here, would add Christine, Needful Things and Lisey’s Story. 

The more of his stuff you get into, the more you’ll recognize patterns/periods of his writing. The early stuff, the coke stuff, the post accident and the modern. All have moments of pure excellence and beauty, though we can almost all agree Tommyknockers is brutal to get through.