In an excellent answer, Gene G provides a deep link into Family Search where an OP can browse images of lists of passengers arriving in Baltimore in the early twentieth century.
If the next immigrant ancestor considered by that OP happened to arrive through New Orleans, then he will need to come back to post a new question asking for Gene or someone else to find the appropriate FS link. Because he (or she) still has no idea how the information provided last time was located.
An alternative approach would be to provide an extended answer on how to filter the list of collections available on Family Search so that some of the genealogical expertise evident here can be shared.
Which type of response truly deserves a {Nice Answer} - one that passes on a few snippets of arcane knowledge or one that empowers the questioner to improve her own practice?