I get my hair done at New Dimensions, on Whitchurch Rd in Cardiff. I have the salon owner, Karen, do it and she's really good, and quite speedy too. Also doesn't see the need for too much unnecessary chit-chat. I have a cut and highlights for £60, so I suppose the haircut is £20-30. Loads cheaper than my last hairdresser (Ken Picton in the Bay), who charged £120!
I used to go to Ocean in Wellfield Road, Roath too. Great service and good haircut. I used to pay around £40. Lots of nice little shops and lovely Makers Gallery nearby too. I miss it (moved away in March).