I just wanted to share some of the references I've been using, in hopes of helping out other accordionists.
There's a really great technique book with exercises for jazz (piano) accordion written by Ralph Stricker and edited by Franck Marocco. It's called "Jazz Theory and Improvisation Studies for Accordion" and it's purchasable as a downloadable PDF at
http://www.roadtomarocco.com/compo.html. There are lots of other PDF books there too, including some of Frank's compositions and covers, and other workshop books.
I've also liked using Romane's book "L'esprit Manouche" even though it's written for guitar, there are lots of great ideas in it.
Finally, for those venturing in to the button accordion I've had some success with Medard Ferrero and Manu Maugain's technique books, purchasable from
http://oscarmusic.com/METHODES/methode2.asp?Cliprov=AXSCXTAFWWQJWHOVMU23:02:20&FAM=42.
Aside from that, if you're looking for accordion sheet music for musette waltzes etc., the forum at
http://swingjo.apinc.org/home.php can make your lives easier!
hope this helps
Brandon
Comments
For the chromatic button accordion, I have been trying to learn using L.O. Anzaghi's "Complete method theoretical-practical progressive for accordion." It's a new reprint of a very old book; it doesn't have a copyright, but it's probably from the 1940s. It has fingering methods and sheet music aimed at practicing those methods. It has piano accordion method too. I bought the book about six months ago from www.sheetmusic.plus.com.
Lorretta