I've had a nice Lachenal Excelcior circa 1870 since November myself, Alison. I think it depends whether you are learning by ear or by reading the dots.
Of course, there is the standard tutorial book by Frank Butler, "The Concertina" but I found it a bit too dry for my liking. I'm trying to teach myself to read the dots as well as learning to play. Its wonderful - and I am gradually improving.
There is the Mad for Trad website for irish music, which has a tutorial facility.
You could also try a message on the International Concertina Association's website ICA .
I know its lonely practicing. There are various concertina groups in England - I have been to two - the West Country Concertina Players in Taunton, Devon and the Chiltern Concertina Group near Bedford. Details of these and others at the ICA site.
Finally, I live in Stratford-upon-Avon (UK). Are you anywhere near? Perhaps we could practice together?
"Well in eighteen hundred and sixty one, roll Alabama roll ...!"
Alan