Red Planet Blues by Robert J Sawyer
Alex Lomax is the only private detective on Mars, scraping a living under the protective dome of New Klondike. Like all the best fictional private detectives he's got a nice line in wisecracks, an eye for the ladies and a reputation that precedes him. New Klondike likewise is a typical frontier town full of fossil-hunters determined to strike it rich, people on the run, corrupt cops. And a writer in residence.
I'm sorry to say I hadn't heard of Robert J Sawyer before this novel, or maybe the name just hadn't sunk in - it seems he's won a whole mantelpiece full of awards over the last few years - but I'll be looking out for more of his work. Red Planet Blues was an assured romp through a twisty plot full of double-crossing, kidnap, murder and mistaken identity. It all starts with what seems like a simple missing person case, but then Lomax starts to uncover things that might be best left undisturbed. Like the truth about what happened to the men who first found fossils on Mars and started the fortune-hunting rush. All this in low gravity, with the added complication of essentially immortal transfers (people rich enough to upload their mind into custom-built and largely indestructible android bodies).
The novel is handled with wry humour, but it has its share of grit and science. If you like your Chandler and Hammett but aren't averse to some future-set extra-terrestrial fiction, I would recommend reading Red Planet Blues.