Back home Landau's life seemed less secure, as she was facing an uncertain future. After her final oral examination in the summer of 1929, she had returned to Halle, where she found part-time work reporting for the local newspaper, the Hallische Nachrichten. In the fall, however, her friend Franz Beidler gave her a message from Einstein. He wanted to meet her in Berlin at his office at another paper, the Berliner Tageblatt. There he asked her to prepare the “Musikalische Zeitschriftenschau,” an index of every article published on music the preceding year, for the next issue of the Zeitschrift für Musikwissenschaft. Landau agreed. With modest financial support for her work, she rented a room in the Berlin apartment of Kaethe Meyer (not to be confused with Kathi Meyer-Baer) while she worked on the task.

Landau took her new job very seriously. With little direction from Einstein, she began scouring every resource for relevant titles and then organizing the listings as clearly as possible through the use of subheadings based on topic. She approached her work with the needs of the researcher in mind: “Perhaps the researcher knew only the title of such an article, or even only part of it, perhaps only the name of the author was known and an indication of the article's content.” For this reason Landau decided she needed to list each article several times, under different headings. After a few weeks Einstein came to check on her progress. He found her in the State Library, across the street from the Staatsoper. He was pleased with her work, recognizing her initiative and independence. In the next few years, he would entrust her with the index's annual completion. Also impressed was Leo Kestenberg, who was then in charge of all things musical in Germany. As a top adviser in the Prussian Ministry of Education, he earned the informal title “music Pope.” Kestenberg wrote to Landau on September 17, 1931, thanking her for her important work creating such a research tool. Journal editors recognized the index's significance as well, contacting Landau directly to ensure the inclusion of their publications. With her growing status Landau was invited to prepare similar listings for other periodicals, the Bach-Jahrbuch and Händel-Jahrbuch.