Can agree with those that recommended Nix's Old Kingdom trilogy and the Codex Alera. Also, though the writing itself isn't very similar to Sanderson's, I HIGHLY recommend the Inheritance Cycle (Eragon).
Also, someone mentioned the epic fantasy list on goodreads. The list of books with interesting magic systems might be of interest as well. Finally, there's a reddit thread with suggestions of books with the best magic systems with a spreadsheet containing a tally of all the votes. Frankly, Sanderson's books were rated the highest, and a number of the other top-rated series were also suggested here too, but there's still a bunch there to look at.