does heffield have a jazz/blue bar or any other unique bar/s ?

could try www.sheffieldjazz.co.uk
http://www.sheffieldscene2.co.uk/sheffjazz/

the Lescar on wednesdays have a jazz night, which can be packed out to get down early.

and there is a jazz bar/resturant up in crooks, can't remember it's name but will try and remember. again you will have to book a table as it's always been fully booked when I gone.

there is a lot of information out there for Sheffields' Jazz scene, just type in sheffield jazz in google or yahoo, if you need any more.
hope this helps. :)