The opening theme song to the anime is the lovely instrumental Silhouette of a Breeze, by Kunihiko Ryo and Hijiri Kuwano.
The first season of the Emma anime was intended to have 36 episodes, but the quality - and the research - sent it so far over budget that it cuts off rather abruptly at episode 12. Victorian Romance Emma Second Act picks it up and finishes the story.
Both series have been licensed for American release by Right Stuf. The first series will be available June 24, 2008.
The first seven volumes comprise the main arc of the story:
Having finished the main story, Kaoru Mori began a set of side stories: Emma Bangaihen (Further Tales). These translations are from IIChan Translation Group.
Kaoru Mori has a one-volume earlier work, "Shirley" - clearly Emma's predecessor. The artwork is simpler, but the story is about another turn-of-the-century English maid (who is Kōta Hirano's third favorite).
There's an interview with Mori (in English) in the spring 2008 catalog from Right Stuf.