Livre d'Or

Folk clubs might be some of the way to go.

In informal mixed singing, playing along with the vocal alto line might often be the most helpful thing you can do -- especially if there aren't many confident altos. The transposition may be a pain at first, but it'll do your sightreading good.

There may well be courses/weekends/clubs/groups etc for grown-up recorder enthusiasts.

I don't have much to contribute in terms of recommendations other than that, having only played recorder in student ensembles that didn't get very far. I do have a treble, so if you happen across any duets and want to play together sometime, and don't mind me stumbling horribly over my fingering, let me know.

I am so very glad you have an instrument to play again. :-)