Shell channel guide is a must,even just for a bed time read.north Brittany and ci.s by cumberlidge has more local info about the towns etc while ashore.2008 seems the latest addition but via Amazon only about £18.Both stop at roughly north west,so no southern coverage.
On the web,play d,eau and jimbsail have some blogs.
We hope to head that way in a couple of weeks for third time so pm if you wish.