Anchor Middle Bar singers are upstairs but still claim to be Middle Bar.
Centre of town. All these things depend on who has arrived yet. But the music sessions are usually in full swing when I arrive - 12pm Fri for the ceilidh in the Anchor Car Park.
The Volunteer is also a singers' session. Opposite Fish Bicycles (about 5 mins walk from town centre.
If you are driving it is best to find free on-road parking in one of the streets opposite the Volunteer or go down to the town centre and look for the Rugby Club (or maybe the Cricket Club though I never parked in the Cricket Club) Charges apply. There is an official car park up near the Connaught Gardens, well worth a visit for the Connaught Tea Rooms - you'll thank me (portion control problems - prepare for big portions)
MAP Rugby club (entrance via Coburg Rd)
Volunteer MAP
Anchor MAP
Clock Tower Tea Rooms MAP

http://www.folkmusicsomerset.co.uk/wessex_acoustic_calendar.php corrected from above