Author Caitlin R. Kiernan (on LJ as greygirlbeast) is in the nice position of having lots of her books in print right now. (I sighted the mass market paperback of her novel Murder of Angels in a Fred Meyer here in Portland, a store her work hadn't been in before.) Of course, availability means nothing unless people buy and try the books, so here are ways to buy 'em:
Silk (originally published 1998)
Threshold (originally published 2001, and for a time in 2002 was pursued by Hollywood for a film version; Guillermo Del Toro was among those interested)
Low Red Moon (originally published 2003, and a particular favorite of hers)
Murder of Angels (originally published 2004)
Daughter of Hounds (her most recent novel, published 2007)
Kiernan also wrote the novelization of the Gaiman-Avary-Zemeckis Beowulf. And she was gladdened recently by this photo a reader sent her of her books on a Barnes & Noble shelf.
Also also currently available: Tales of Pain and Wonder, I think Kiernan's favorite of her short story collections, finally revised the way she wanted it (an earlier edition had a lot of errors that slipped in after she'd proofed it). Harrowing reading in a beautiful book.