Shave and a Haircut

Undead rogues especially: "OMG my hair is not done yet!" *Vanish*

There's the joke that female Blood Elves like to tell: "I went to Undercity to get a facial. Ha! Have you seen these people? I said, 'You don't have a lower jaw and you're going to give ME a facial?' She got mad...at least I think she did. You ever heard someone talk without a lower jaw? 'Rawe-rau-werew' Ho-ho! She sounded like a murloc!" Not directly related to hair, but apparently some of them do care about thier appearance. Perhaps trying to conserve what they still have left.

A list of all barbershops and their barbers (if applicable):

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• Trade District, Stormwind City (Jelinek Sharpshear);
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• The Commons, Ironforge (Pella Brassbrush);
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• Cleft of Shadow, Orgrimmar (Bebri Coifcurl);
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• Trade Quarter, Undercity (Naznik Sureshave);
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• Area 52, Netherstorm (Pulik Swiftsnip);
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• Cosmowrench, Netherstorm (there is no barber, but a chair);
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• Dalaran (Kizi Copperclip).
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There are two barbershops for each faction and three neutral ones.
Edit: Added the barbershop in Cosmowrench.