As a non-Dub I've no great agenda here, just struck me while listening to the bould Mr. Dempsey (Damo, not Ian) that the Northsaoide might be punching above its weight in this regard.
So if we take central as between the canals, and the Liffey dividing the rest we have:
North: U2 (where they grew up, band formed etc), Damien Dempsey, The Frames (?) - Glen Hansard anyway. U2 'spin offs' like Gavin Friday & Guggi (harsh I know), Boyzone (gulp!)
Central - Imelda May, Mary Black (?), The Script
South - Sinead O'Connor, Phil Lynnott, The Thrills (briefly)
Interesting, he spoke in a fairly refined manner (untypical of what latter-day Sheriff St would have been depicted as). I think Ronnie Drew was south (Dun Laoghaire maybe originally - I know ultimately Greystones).
If we branch out to sport, Gilesy was central (near 4 courts), Ronnie Whelan I think was Ringsend? (you could nearly call central - though 'beyond' the canal), Dunphy north (Dromcondra). "The Dubs" of the 70/80 were mainly north - not too many central - not much GAA in central - maybe O'Connells school that's right beside Croke Park backing onto the canal.