"I am looking for a marriage record between John Luber and Susanna Schaus probably between 1844 and 1846 ... By 1846, the couple lived in Watertown (Jefferson Co.) and had their first child in December 1846. They were Catholic."
This is an old post - but I wonder if you have since checked the records of St. Bernard Catholic Church in Watertown (their office, or the FHL microfilms). The parish was already organized with a frame church built by about 1845 (according to a photo on their website). If their first child was baptized there, you may come up with other research hints from those records.
I have not indexed a marriage announcement for them from the German papers, although their are such announcements dating back to 1845 - placed by the person pronouncing the marriage or the couple.
"Milwaukee's German Newspapers; an index of death notices and related items" (1844-1950).
Gary Rebholz, compiler/editor
Indexing Milwaukee's German newspapers continuously since 2007... helping family researchers collect evidence of our historic German-American culture.