I would recommend Cielo I think it's called. It' on Calle 7 1/2 block back from the waterfront. Right across from the Calle 7 entrance to Punta Langosta shopping mall and you can park free there and just walk across the street. The stylist is from Texas and does good work.
The shop has some kind of sculpture like an angel hanging outside. I'm sorry I don't remember the stylist/owner's name at the moment as I've only had a chance to use her once so far. But someone else will probably provide this momentarily. Or try a search of the forums as there was a thread about this awhile back.