Passenger list missing details - what next?

[jeannie1000cc]

I have found my immigrant ancestor's passenger list entry, but unfortunately place of birth/emigration simply listed as Germany. 

I have every conceivable US document for my ancestor, right down to Catholic Church records and Naturalization papers. Still no idea where in Germany (Prussia) he was from. 

I have read that the reference series "Germans to America" contains specific origins of all emigrants. If there was no further detail on the list I have (for the ship "Bremen", dep. from Bremen, Germany; arr. NYC Feb.11 1873) will there be more in emigrant records, and where do I look for them?

Any pointers in the right direction welcomed....