You may be looking in the wrong place. For online case info, try:
The information presented here is general in nature and is not intended, nor should be construed, as legal advice. This posting does not create any attorney-client relationship with the author (who is only admitted to practice law in the State of California). For specific advice about your particular situation, consult your own attorney.
Your case number would be found in the superior court in the county where the case is filed. There is not a uniform system in California to find a family law court case number. Additionally, some courts will not allow a name search unless you personally go to the court house. For example in Los Angeles, you can use a case number to look up the status of a case through their online system, but if you only have the last name of the party, you must go to the courthouse to look up the case number.
The response above does not form an attorney-client relationship. This answer may or may not apply to you and should not be relied upon as legal advice.
If your case is a paternity action you cannot find out about it online. Paternity actions are confidential and can only be accessed by the parties or their attorneys.