Urban growers, here are some links that could help you get started in your backyard.
A great place to start is the UC Master Gardener website. The UC Master Gardener Program is a public service and outreach program under the University of California Division of Agriculture and Natural Resources, administered locally by participating UC Cooperative Extension County offices. They are available to answer your growing questions.
For General Sources, Production Management and many other links, look at:
More Avocado Resources for the California Backyard Orchard
For Avocados in Orange County look under Master Gardeners Orange County Edible Plants.