Generally without going out the graveyards themselves this might be a difficult project for someone, the time involved would be phenominal.
In 1900 the Parish of Tisaran was surveyed for readable gravestone inscriptions, nothing about Ferbane. These are available with a membership with an expensive UK firm who has the rights to the information.
However, local museum or heritage societies and schools may have had their own projects made into journals. Look to the Library on line and see what they have under 'local studies'. You may need to email to ask.www.offaly.ie
under county council is located in Tullamore
I forgot www.igp-web.com
+ county has archives with photos from graveyardswww.from-ireland.net