The Lassie series does not have a new book coming out soon. The latest book, Lassie: Danger at Echo Cliffs (Book 4), was published in January 1996.
The first book in the Lassie series, Lassie: Under the Big Top, was published in August 1995.
The Lassie series primarily falls into the General Fiction genre. This middle grade series was written for ages 8-12, but can be enjoyed by older readers as well.