Here's a list of this year's six Hugo nominees for best novella, with some links to the stories.
"The Ice Owl", Carolyn Ives Gilman (F&SF 11-12/11)
"Countdown", Mira Grant (Orbit Short Fiction) - link to buy e-book
"The Man Who Bridged the Mist", Kij Johnson (Asimov’s 10-11/11)
"Kiss Me Twice", Mary Robinette Kowal (Asimov’s 6/11)
"The Man Who Ended History: A Documentary", Ken Liu (Panverse Three)
Silently and Very Fast, Catherynne M. Valente (WSFA)