There are 3 books by Phil T. O'Brien on BookOrb. A strong starting point is Cullinan Foible (2014). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has Phil T. O'Brien written?
BookOrb lists 3 books by Phil T. O'Brien.
Where should I start with Phil T. O'Brien?
A good starting point is Cullinan Foible (2014).
What is the Phil T. O'Brien books in order list?
In publication order: 1. Bullets, Badges, and Bullshit (2006), 2. A Tree in the Wind (2006), 3. Cullinan Foible (2014).