Ancestry.com now has "all readily available U.S. passenger lists from 1820 to 1960" digitized and indexed. This includes those post-1924 Ellis Island records you've been dreaming about. You can search the entire Immigration Collection for free through the end of November.
More than 100 American ports of arrival are represented in the compilation including the entire collection of passenger list records (1892-1957) from Ellis Island, a historic landmark and icon of immigration. The collection also accounts for popular ports in Boston, Baltimore, New Orleans and the Angel Island receiving station in San Francisco. [Link]