I would go down to the Open Mic session at Number 11 on Upperbridge where you will find guitar players ranging in age from about 14 - 60+ and I'm sure someone there will be willing and able to point you in the right direction. It starts at 8.30 but you need to be there early doors as it's only a small room and soon gets full. The next session is Thursday January 10th.
To follow a couple of the suggesstions already made - I doubt Sheila at the Nook will be able to suggest anything other than what has already been mentioned here and I wouldn't hold out much hope at the TIC. I would echo the suggestions of the Music Room in Cleck and Eagle Music at Netherton.
There'll be some workshops at the next folk festival (May 9th - 11th) but I can't tell you exactly who or what at this early stage.
Good Luck
Cath