The Rapparee

The galaxy is full of wealthy planets and haughty aliens who guard the technology of interstellar travel. Earth must pay a price for use of the space drive, and this rubs Paddy Blackthorn the wrong way- so he sets out to steal the secret. The powerful Shauls capture and dump him on a barren planet - yet here he acquires five golden bands containing the very data he is after. The information is coded - and while Paddy solves the puzzle he must evade a galactic manhunt!

- summary from the official Jack Vance website