Filing a mechanics lien enforcement requires filing a lawsuit in the state district court in the county where the lien was filed. Because it requires a lawsuit, lien enforcement is usually done by an attorney. Generally, businesses aren't able to file lawsuits on their own, and while individuals can file lawsuits in their own name, it's almost never wise to do so.
For help finding the right lawyer: Top California Construction Lawyers. This article should be useful, too: What Is “Enforcing” a Mechanics Lien?