The U. S. Library of Congress
and the Ira Gershwin Gallery has an online exhibit of maps of Los Angeles
, most dating from the first half of the 20th century. Maps are zoomable and downloadable in Jpeg2000 format. There are still a few maps that are awaiting approval to be placed on the website, including a Soviet topographic one of Los Angeles produed in 1961.
By way of MapHistory