Need to file a mechanics lien in Contra Costa County? Here's what you need to know to record your lien with the Contra Costa County Recorder.Use this form to file a mechanics lien in the state of California. A California mechanics lien is a powerful tool to help contractors and suppliers get paid. The notice must contain the names of all parties to the action and a description of the property. Fill in the blank Notice of Mechanics Lien form formatted to comply with all California recording and content requirements. Easy-Fill: Fill out the form online, then print and mail it to CSLB. PDF: Print a blank form, then fill it out and mail it to CSLB. Prejudgment interest from the date the lien is recorded may also be included in a mechanics lien. Contra Costa County.