Stolen / Kelley Armstrong.

Enhanced descriptions from Syndetics:

International acclaim for Kelley Armstrong's sophisticated debut novel, Bitten, is steadily growing. It was in Bitten that thirty-year-old Elena Michaels came to terms with her feral appetites and claimed the proud identity of a beautiful, successful woman-and the only living female werewolf. In Stolen, on a mission for her own elite pack, she is lured into the net of ruthless Internet billionaire Tyrone Winsloe, who has funded a bogus scientific investigation of the "other races" and their supernatural powers. Kidnapped and studied in his underground lab deep in the Maine woods, these paranormals-witches, vampires, shamans, werewolves-are then released and hunted to the death in a real-world video game. But when Winsloe captures Elena, he meets his match. Suspenseful, chilling, and witty, Stolenis a novel of rich and amazing versatility.