The first is Dwight V. Swain's Techniques of the Selling Writer. I have the older edition with the yellow cover. No matter which edition you have or purchase, it is an invaluable treasure trove of information on writing craft that just really isn't being taught today. Need to know what a Motivation-Reaction Unit reversal is? This book will tell you that it's when your character reacts to something before it's within the realm of awareness.
I jumped three feet in the air and scampered backwards at the sight of the fire breathing monster standing in my bedroom doorway. This is a MR reversal because you have to SEE the monster, then you can REACT to it. For those of us who startle easily, think of it like having the "oh you startled me" moment without seeing or hearing anything. It'd be pretty strange to walk around your house going "oh you startled me" for no reason at all. People might think you perhaps were suffering from some ailment. There's usually a noise, the glimpse of someone out of the corner of your eye, something that causes you to have that jerking startle reflex. What you see/hear is your motivation. The jump in your chair is the reaction.
Your reader also needs these in order, because if your character runs screaming in horror, and then sees the zombie eating his best friend, the reader is either going to wonder if the character is physic or just a drama queen. :)
The other big lesson I learned here was a scene set. Think of the page as an empty stage. Everything you put on the page "sets" the stage. A lot of settings are universal. Tell your reader you're in a school and the desks, white board, projectors, books, noises of scuffing chairs across the floor will fill in themselves. But the reader has to know they're in a school. Starting your writing out with dialogue is basically putting a disembodied voice on an empty stage. So dress the stage.
In the stage production of Phantom of the Opera begins, you see the chandelier drop down over the audience. It's rather dramatic. It also tells you where you are (an opera house with a big chandelier) and sets the tone that there's danger and mystery. This is the scene set.
The other book is Orson Scott Card's How to Write Science Fiction and Fantasy. (I have the older version here. Both are good.) If there's one beef I have with the book is that he uses his own books as examples. The best writing instructors will find examples from other people's work to prove their point. But otherwise, the information is excellent and I very much recommend this book.
Writing craft never goes out of style. Though fashions may change, good craft/good writing will always be read. If that weren't the case, then why do so many people still enjoy Austen, Tolkien, Dickens, and Poe? Or to keep it close to the Science Fiction/Fantasy genre, Timothy Zahn's first Star Wars books (AWESOME writing!) or Feist's older trilogies. (I could totally go on... Anne McCaffrey, Mercedes Lackey.... you get the picture.)