I've been enjoying playing Billy Pigg's tunes this winter. And decided to extend myself and actually purchase his tunebooks offered by the Northumbrian Pipers Society. I think there was a discussion some while ago about a couple of other worthwhile books the Pipers Society offer that translate well to concertina. I'll take suggestions: if I'm in for a penny I might as well be in for the pound ordering these interesting books. The Society has about 4-5 pages of books offered on their website.