There are 3 books in the Solar Queen series. The newest book is Voodoo Planet which came out in 2014.

1
Sargasso of Space

Book cover of Sargasso of Space
Stellar exploration—and depredation—in the exciting first novel in the Solar Queen series from a “superb storyteller” (The New York Times).
 
In the future, venturing out into the stars is more than a way for humanity to chart the cosmos—it’s big business. Every time a new planet is discovered, the highest…
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2
Plague Ship

Plague Ship
Rip¿s dark fingers halted their circular motion. ¿Dane ¿ he warned ¿don¿t you go talking against this venture. We got it soft and we¿re going to be credit-happy¿if it works out¿¿' (Excerpt)

3
Voodoo Planet

Book cover of Voodoo Planet
The sequel to Plague Ship, Voodoo Planet features Dane Thorson, a young man fortunate enough to land a job on the Free Trader ship, the “Solar Queen.” Plying their trade among the stars, Free Traders visit planets–known and unknown–in search of profit. Captain Gaelic and the ship’s medic, Tau, are…