A lot of people head for Lisdoonvarna after the Fleadh. The Matchmaking Festival is on there for the whole of September, and sessions abound.
There used to be a lovely session in Bell Harbour, not far from Corofin, Co. Clare.

It's been 4 years since I hit a session in Clare, so the venues could shift (as they do), but Tommy and Siobhán Peoples used to have one in Brogan's, O'Connell St, Ennis, and as far as I can recall, Declan Brandon's at the top of the street used to be a great hangout.

If P.J. Curtis sees this, maybe he can fill you in on more up to date stuff.

B.