E.C. Tubb 
Stellar Assignment [EPUB ebook] 

Trapped in the economic rat-race of the 21st century Kevin Blake had little going for him but an over-active imagination: an attribute which brought him to the notice of Paul Trevainen, who made Kevin an offer he couldn’t resist. On the face of it the assignment was simple – to find the billionaire’s daughter, bring her back to Earth and collect a dazzling reward. But Crystal was wilful, stubborn and hard to find. The quest forced Kevin to become an advocate in an alien court, turned him into a hunter, and made him the captive of giant, money-hungry frogs, a rebel against established authority, a fugitive, a criminal and in general one of the most harassed young men ever to have longed for adventure.