There are 8 books by G O'Callaghan on BookOrb. A strong starting point is The Castaway Scouts (2007). The bibliography below is in publication order, with series grouped in reading order.
Standalone books
Frequently asked questions
How many books has G O'Callaghan written?
BookOrb lists 8 books by G O'Callaghan.
Where should I start with G O'Callaghan?
A good starting point is The Castaway Scouts (2007).
What is the G O'Callaghan books in order list?
In publication order: 1. The Castaway Scouts (2007), 2. Ravenlock (2007), 3. Planet Miners (2007), 4. The Cruel Sky (2007), 5. Yanada (2007), 6. Tektite (2007), 7. Jaunter (2007), 8. Hypnotic Augmentation (2007).