According to the Four Winds website http://www.fourwindsgrowers.com/ you can now order from them directly online and have the order shipped to your home. You can also find online a list of nurseries that carry their citrus.
The other area citrus grower that I know of is Menlo Growers in Gilroy. I thought they were just wholesale but, according to their website, they too ship retail orders made online. http://menlogrowers.com Their website is not complete, so you are best