The Historical Society of Southern California has a list of over 30 publications for sale.
The most recent books the Society has published are by Tom Sitton, The Courthouse Crowd: Los Angeles County and Its Government, 1850-1950 (2013) and Judson Grenier, George Carson: Los Angeles Pioneer (2014).
Use this HSSC Book Order Form (PDF) to order books. Please indicate on the form if you are paying by check or credit card.