How do I file a lien on a property?

[Jessica Martin]

Ok, so my husband and I lent a couple grand to someone for some of the closing cost on a house. Of course we have a signed document stating how much was borrowed, by whom, and when it was to be paid back. The due date was April 30th. We sent her on email about 3 weeks ago as well as a final reminder to please pay or we would unfortunately have to take it to a level I had hoped it would not and file a lien on the property. She is flipping this home and will probably go up for sale soon. 

Can someone please let me know how to file a lien on the property. I contacted the county but they said they are not allowed to tell me how to do this... so I dont even know where to start...

Thanks so much!