I found this phone number and address for your county you may want to start here.
Main Street Courthouse Family Law/Adoptions/ Criminal/Juvenile
495 Main Street
Placerville, CA 95667
(530) 621-6426
El Dorado County Superior CourtsJust give them a call most of the time they are nice and helpful you will probably have to fill out some forms and if you have no idea where the bio dad lives you will eventually have to place an ad. Some of the mom's here that have helped me like AJBSMom and crystaly you can go back and look at what they had to do that may help. Also the Nolo book (you can usually check it out from the library to get started) for California Step Adoptions is really helpful just remember it may not go step by step in your county the way it goes in that book.