A direct continuation of Ultimate Note is kind of up in the air because that production company lost the rights to the author. BUT the author is the chairman of the production company, NP Entertainment, which produced Reunion: Seasons 1 & 2, Mystic Nine, and Tomb of the Sea. NP Entertainment also has plans for more television adaptations of other books (the shows are based on a series of books called Daomu Biji (盗墓笔记) or The Grave Robbers' Chronicles as well as its sequels and prequel. )
In the meantime, you can read the direct continuation of Ultimate Note in vol. 8 here. Ultimate Note is pretty close to the novel, however, supernatural stuff does exist (ghosts, zombies, etc.)
If you want just want to watch the next available show, the order to watch is here.
If you want to read all the books from the beginning, the order is here.