There are 2 books by Dennis L. O'Brien on BookOrb. A strong starting point is From Ludington to the Final Crucible (2003). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has Dennis L. O'Brien written?
BookOrb lists 2 books by Dennis L. O'Brien.
Where should I start with Dennis L. O'Brien?
A good starting point is From Ludington to the Final Crucible (2003).
What is the Dennis L. O'Brien books in order list?
In publication order: 1. From Ludington to the Final Crucible (2003), 2. To the Final Crucible (2003).