There are 5 books by Josh O'Brien on BookOrb. A strong starting point is Supercenaries (2013). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Showing 3 of 5 titles.
Frequently asked questions
How many books has Josh O'Brien written?
BookOrb lists 5 books by Josh O'Brien.
Where should I start with Josh O'Brien?
A good starting point is Supercenaries (2013).
What is the Josh O'Brien books in order list?
In publication order: 1. Underground Santa Claus (2012), 2. Underground Santa Claus (Illustrated Edition) (2012), 3. Supercenaries (2013).