Out of the Shadows by Tim Lebbon
When a shuttle crashes into the mining ship Marion, the miners learn that there was more than trimonite deep in the caverns of planet LV-178. There was evil, hibernating--and waiting for suitable prey. Quickly they discover that their only hope lies with the unlikeliest of saviours... Ellen Ripley, the last human survivor of the Nostromo.

Sea of Sorrows by James A. Moore
The Weyland-Yutani Corporation has secrets of its own, as Decker discovers when he is forced to join a team of mercenaries sent to investigate an ancient excavation. Somewhere in that long-forgotten dig lies the thing the company wants most in the universe--a living Xenomorph. Decker doesn't understand why they need him, until his own past comes back to haunt him. Centuries ago, his ancestor fought the Aliens, launching a bloody vendetta that was never satisfied.

River of Pain by Christopher Golden
Protected by the Colonial Marines, the colonists of planet Acheron seek to terraform the storm-swept planet. Two such residents are Anne and Russell Jorden, seeking a fortune that eluded them on Earth. The wildcatters discover a vast, decaying spaceship. The horseshoe-shaped vessel is of particular interest to Weyland-Yutani, and may be the answer to their dreams. But what Anne and Russ find on board proves to the stuff, not of dreams, but of nightmares.