Legal Question in Civil Litigation in California

The place where you file is called the "venue." You have several venue choices in contract cases, although it may turn out to be the same place for all the choices. Unlimited Jurisdiction breach of contract cases can be filed in the Superior Court for the county in which the contract was formed, the county in which it was to be performed, or the county where the defendant resides. Once you determine the county, most counties have several branches of the Superior Court in which you can file. Which branch you file in is the subject of local rules that you would need to consult once you find the proper county. If the zip code you give is in the proper venue for your case, you would file in the Alameda Superior Court at the Rene C. Davidson Courthouse on Fallon St. in Oakland.

You want to file a "breach of contract" action. Breeches are pants.

.........and for Contra Costa County, the main courthouse for civil cases is on Court St. in Martinez, although the branch court in Walnut Creek may accept the case.

In Alameda County, you can file at any of the Courthouses [go to the court web page for addresses], and you will be assigned to one of them on a random basis. Be sure to prepare a civil cover sheet and Summons.