There are 150 books in the Star Trek: The Original Series series.
The Star Trek: The Original Series series does not have a new book coming out soon. The latest book, In the Name of Honor (Book 97), was published in January 2002.
The first book in the Star Trek: The Original Series series, Star Trek: The Motion Picture, was published in December 1979.
The Star Trek: The Original Series series primarily falls into the Space Opera genre.