Not all online services that you find useful for genealogical research will specifically be genealogical sites. For instance, try using a search service to look up a name. While many hits will come from recent events, you will also find that some results are of genealogical interest.
Just remember to try many variations when search, including unquoted, quoted "forward" or "backward" (setting the surname used in many cultures either at the end or the beginning, respectively), and remember to try variations on the name and/or nicknames.
Please note that all of these will take you away from the SBCGS site.
For all major libraries and for many smaller ones, the days of having to physically look through the stacks for research is quickly going away. While certain libraries have manuscripts that are too ancient or fragile to be placed on-line, or may not have the staff or money to do so, the card catalog itself is almost universally now a computerized and on-line feature. So if you can't obtain the actual text on-line, you can research the books, microfiche/microfilm, periodicals, journals, or whatever else may prove useful, and do that initial leg-work before you head to the library.
Beyond the SBCGS library, some libraries that are local to the South Bay area of California include the following.
Genealogy is not always a matter of finding information that directly relates to your ancestors. Sometimes the non-direct information is important too. And that means historical sites — learning how the people lived can tell you a lot, and may provide clues to understanding your ancestor's actions, habits, and travels. While many genealogical sites will have history, these links are specifically for historical sites that can provide insight on your ancestors.
Beyond libraries and histories are the indexes, search engines, and directories that inform your research. While most of us know about the major search engines and use them all the time, there are lesser-known resources that are all too frequently missed. Some of those are listed here.