If you like Sabriel by Garth Nix

If you liked the Abhorsen Trilogy, you also want to try (if you haven't already) some of Garth Nix's other series such as the Keys to the Kingdom and the Seventh Tower.

Also, here are a few other fantasy titles you may enjoy.

The Amulet of Samarkand: Book One of the Bartimaeus Trilogy by Jonathan Stroud.
Nathaniel, a magician's apprentice, summons up the djinni Bartimaeus and instructs him to steal the Amulet of Samarkand.

The Golden Compass by Philip Pullman.
Accompanied by her daemon, Lyra sets out to prevent her best friend and other kidnapped children from beingthe subject of gruesome experiments in the Far North. This is Book 1 of a trilogy.

The Merlin Conspiracy by Diana Wynne Jones.
Roddy and Nick, two teenagers with recently discovered magical powers,find that they must work together to save Roddy's home world of Blest from destruction by power-hungry wizards.

A Wizard of Earthsea by Ursula K. Le Guin.
A boy grows to manhood while attempting to subdue the evil he unleashed on the world as an apprentice to the Master Wizard.
The first in a series.

Outlaws of Moonshadow Marsh: Sign of the Qin by L.G. Bass.
In long-ago China, Prince Zong, the mortal young Starlord chosen to save humankind from destruction, joins the twin outlaws, White Streak and Black Whirlwind, to fight the Lord of the Dead and his demon hordes.

Dragonsong (part of a series I loved!) by Anne McCaffrey.
Forbidden by her father to indulge in music in any way, a girl on the
planet Pern runs away, taking shelter with the planet's fire lizards
who, along with her music, open a new life for her.

Artemis Fowl (part of a trilogy) by Eoin Colfer.
When a twelve-year-old evil genius tries to restore his family fortune by capturing a fairy and demanding a ransom in gold, the fairies fight back with magic, technology, and a particularly nasty troll.