Much of my SF books lately are eBooks. One primary source is Baen Webscriptions. One of the books was Tinker by Wen Spencer. This book is well written and totally engrossing. This is magic as science along with regularly science and then there are the elves....
Besides Tinker, Wen has also written the 'Ukiah Oregon' series which is a different take on aliens and alien invasion. Wen's writing in all cases is excellent
When I first picked up Archangel by Sharon I was mesmerized. This is one of the few books I have pushed on other people. It is probably one of the best books I have ever read. Archangel was followed, by Joavah's Angel and The Allelulia Files all equally engrossing. The series has since expanded to five with addition of Angelica and Angel Seeker.
Sharon has written other books all well written and worth reading. You owe it to yourself to try Sharon.
Sarah Zettel writes fascinating books that explore the ideas of artificial intelligence in new and different ways. Reclamation, her first book is on a different topic but still worth reading. Fool's War and Playing God each explore the topic in different ways. Sarah has since written other other books equally good reads. In the last couple years Sarah has written a fantasy series, about the world of 'Isavalta'. I am very picky about that fantasy books I like. Sarah's are definitely not your run of the mill sword . sorcery. There is sorcery but these are mainly character driven books.
Jo Clayton writes both SF and Fantasy, although sometimes she manages to put them together. All of her work involves strong but human woman heros. Jo's works are good adventure stories which I enjoy a lot. My favorite books are the Diadem Saga. Unfortunately for us all Jo is no longer with us.
Jack Chalker is best known for his Well World series but as far as I'm concerned the Flux and Anchor series is much better and my personal favorite. All of Jack's stories seem to involve some sort of physical morphing of his characters.
Melissa Scott writes good stories, some about our cyber future.
Julie E. Czerneda, Walter Jon Williams are other authors worth looking into