One of my frequently used methods for intricate masks such as hair is to go to the channels tab and duplicate the channel which has the most contrast, apply levels and further enhance the contrast, then click on the 'make channel a selection' button. Once the selection is turned into a mask for what ever layer you are working on you can use the brush tool set to overlay blend mode and brush white or black on the mask itself to remove the grey areas and you are left with a quick and intricate mask. Feather the mask to fine tune the blending of that layer.
This method is largely dependent on a strong color contrast between the subject and the background to be able to separate them using channels. It doesn't work for everything but when it does work it can be very helpful.
