Lien Laws

Does anyone have any suggestions where I can go (other then attorney) such as a website or ? to obtain filing of contractor lien procedures in a particular state? Laws differ from state to state. Have a contractor threatning to file a lien on rehab work even though he never completed work, and all work was agreed to via verbal agreement, no contract! I’m just looking for the procedures in this state (Louisiana), as I know in some stares you have to file a notice to owner before work commences. Any ideas? Help!