try googling the phone number for the Catholic Arch Diocese for Zahle. There should be someone there that is in charge of records.
If you still know of any family in Lebanon they can usually go there and get the records. All baptism, marriage and burial records should either be at the Church or the Arch Diocese.
Also all major cities like Zahle should have a local council where all birth, death and land transactions are kept. These are usually a little harder to access as you need to send the Mukhtar(Mayor/Justice of the Peace)to get them.
If you have any other questions just ask away and I'll try and help best I can