Hello Ric,
I too am interested in Ahern, Ahearn, A'herne family of County Clare. The various spellings have corrupted the family branches over the years and it makes it a little difficult to research them. It's always a good idea to throw a VERY large net when looking for them........... many of the early Irish were unable to read or write, as you know, and so it was not ususual to have people, even in the same family, spelling their surname differently. When considering the possibilities, just say the name out loud with an Irish accent and consider whether or not it "sounds" like a possibility(and DO consider all possibilities).
I have one branch of my family who were Ahearns (and various other spellings) and migrated to Australia. But of greater interest to me now is that I have ancestors of another surname altogether whom I had researched diligently for years and was quite satisfied that I had all the available information about them. All the children of that family (so I thought) also migrated to Australia. Then, thanks to an incredibly alert and kind Clare Librarian (don't we just love those Librarians at the Clare Library! Such a hard-working and professional bunch!) my previous research exploded into several different directions. The Librarian noticed a familiar surname (mine) as he went through some records. He had previously answered some questions for me regarding Clare family and local history. He followed up on the clue and "found" a missing child from my Clare family about whom I had never even heard. That led to my discovering that this other child had migrated to the USA and had not come to Australia along with the others, eventually llsing touch altogether. An entire new family branch!
She had married an Ahearn (various spellings turn up in the records even "Heron!"). The Ahearn she married was also Irish. So far I have been unable to find a record of marriage for the couple but Kilrush is an area cropping up in my research with requency.
Because most of the Clare records have not yet been released, I suggest that the information you wish to find, may only be found within the Parish records. I shall keep watching this thread with interest to see if you come up with anything else about your Ahearns (Aherns, A'hernes, Herons etc) and if I find anything which I think may be of assistance to you I will post it here for your perusal.
Good luck! Please contact me directly if you wish to collaborate.