Who do you consider a Great Author of the last 50 years or so (first well-known work after 1970)? I'd like to get a feel for who's who in modern literature. Any language/culture. Fiction only.

Roger Zelazny. Even though he started in the sixties, he was active through the 70s, 80s, and early 90s until his death. Fantastic world building and characters that feel very much like real people.