Using the extract tool for people withblowing hair

I am trying to make a portrait of a child for her parents. I am using the extract tool to take her out of the picture so I can place her onto a black background and turn her image greyscale. Th eproblem is that her hair was blowing when I took the picture and there are parts of the picture where you can see through her hair. When I extract her all of her hair is there, but so is the background behind her hair and also along the edges. Is there a way to cleanly extract her and her hair without the background. I have been using photoshop for about 6 months, so I can do some tasks easily, but some I will need some more detailed instructions. Thanks in advance for any help.

and you can just use the blending modes on the layer which contains the portait? or is there "too much happening" behind her hair"

There is kind of a lot behind her hair. The picture was taken on a playground, so you can see some blue sky and some multi colored playground equiptment.

There really isn't an "instant" way to do it. A good result requires some manual work.

Here are a couple of resources for "hard to get to" selections such as hair.

http://home.supernet.com/~guntcher/Mask/Lum_Mask_APS.htm

Deke Mc's site
as a PDF
http://www.dekemc.com/Dwnloads/Ph55Esup.pdf

Thanks for the info