Angelic is a short story narrated by the Angel Eve set in Kelley Armstrong's Otherworld series.
It's a limited edition book, and by all accounts sold out before publication through the publisher's website. That's why Amazon has none, and indeed didn't have enough to fulfil the preorders they accepted.
It is a very short story. The whole thing is maybe 100 or so pages long, and in quite big font. It expands on Eve's role as the designated "bad" Angel and her frustrations with the expectations everyone has of her. It's a nice adjunct to the series, popping in to see how the ghost world is getting on, but it's certainly not essential to the growing Otherworld background. And it is very, very, short.
Anyone selling this as new simply has a copy that they've not opened and have decided to resell straight away. The book had a very limited print run at around 2000 copies and there's currently no indication that more will be produced.