Spaceman Blues by Brian Francis Slattery was published by Tor in 2007 and is no available for free download at Tor.com.
Synopsis:
When Manuel Rodrigo de Guzmán González disappears, Wendell Apogee decides to find out where he has gone and why. But in order to figure out what happened to Manuel, Wendell must contend with parties, cockfights, and chases; an underground city whose people live in houses suspended from cavern ceilings; urban weirdos and alien assassins; immigrants, the black market, flight, riots, and religious cults.
Painted in browns and grays and sparked by sudden fires, Spaceman Blues is a literary retro-pulp science-fiction-mystery-superhero novel, the debut of a true voice of the future, and a cult classic in the making.
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