Depends on what you're looking for. I have a friend who does a lecture on the Lord Randall variations throughout Europe. And it seems to me that fiddlers tunebooks from previous centuries show some French/Italian/etc crossover. And I heard another friend lecture on a 'style' of Welsh poetry / songs / tunes that actually trace back across Europe and the middle East to India of the something-th century. (Verses that muse, "If all the fields were paper, and all the sea ink, and all the reed-beds pens ..." type of thing.

I did do some prodding on this subject a few months back. Alan Stivell actually asked me if I thought there was any mileage in a project trying to identify one pan-celtic tune and working up a trans-national project on it. But I couldn't find anyone (I did ask a number of experts) who thought that we'd be able to find a tune that was common across enough of the celtic nations.

sian