Baccano! is written by Ryogo Narita (writer of Durarara! you can read my review of it here) and illustrated by Katsumi Enami. It was first published in 2003 and is still on going. There is a two volume manga that is a side story for the series there is an other manga that is currently running that is an other side story for the series. There is also an anime that runs 16 episode, it came out in 2007. (I did a review of the anime you can check that out here) There is also are two drama CDs with two side stories on them. Also, there is a DS game that fallows the events of the anime and the second and third book.
Baccano! is based of a light novel series of the sames name. The series ran for 21 volumes. It was written by Ryogo Narita, the creator of Durarara and Vamp!. Besides the anime the series has also spawned two manga series. The anime came out in 2007 and ran for 16 episodes.