Designed as an Introduction to the world of Eberron and is intended for a party of four 1st-level characters. This adventure takes place in Sharn, the city of Towers. It begins, as many incidents in the City of Towers do, with a corpse. A warforged assassin, a mysterious blank book, and an offer from a House Cannith heir leads the adventures into the depths of Sharn--eventually to an ancient ruin dating back to before the creation of the Kingdom of Galifar.
Along the way, if the adventures are successful, they recover a lost schema--a part of a pattern used by artificers to craft magic items. They also learn that many different agencies are interested in this relic, including those loyal to the various House Cannith elders and agents of the infamous Lord of Blades.
Eberron Campaign Setting was published in 2004.
iamn0twill has played this adventure and would recommend it.
Read it, running it as the opener to an upcoming Eberron campaign. It's got some good elements to be expanded upon.