The House of Arden series does not have a new book coming out soon. The latest book, Harding's Luck (Book 2), was published in January 1909.
The first book in The House of Arden series, The House of Arden, was published in January 1908.
The House of Arden series primarily falls into the Fantasy genre. This middle grade series was written for ages 8-12, but can be enjoyed by older readers as well.