Online availability of docket sheets and underlying documents varies greatly from state to state and court to court.
For California trial, appellate, and supreme court docket information, go to the individual court's website. A list of links to each court's website is maintained by the California court system's Find My Court page.
In general, if the particular court makes docket sheets or the underlying electronic documents available online, there will be a link or tab on the home page to access the search page - look for a link or tab for "Case Information," "Online Case Search" or similar wording. Practice varies widely, e.g. -
The LA Law Library maintains one of the most comprehensive collections of California Supreme Court and Courts of Appeal briefs, dating back to the establishment of the state. The collection is being digitized for online access.
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