Digital BW, The Print

BW comprehensive info resource at RetouchPRO: 

("safe" tinyul preview link) - http://preview.tinyurl.com/23en42

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Actions: There are a boatload of BW actions at 

http://www.atncentral.com

KentC's action is prety slick. It's a twist on the dual hue/sat 
adjustment layer Russell Brown technique mentioned previously. Kent 
uses a Selective Color AL in place of the bottom HS AL. 

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Image > Calculations: 

There are a lot of creative potential using this command, however 
intuitive "is is NOT" and it's a bit cumbersome to use, especially 
for those who are indecisive, like me.

http://forums.dpreview.com/forums/read.asp?forum=1006&message=17082710

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Contrast masking can be useful method...

http://www.outbackphoto.com/workshop/photoshop_corner/essay_06/essay.h
tml

...as can luminoscity masking...

http://www.goodlight.us/writing/luminositymasks/luminositymasks-1.html

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FWIW I prefer to use an action to create individual layers from each 
RGB channel plus CMYK's K channel (set to Multiply). This is like 
employing a combination of Calculations + Channel Mixer. It enables 
one creativity and flexibility via masks, blend modes, opacity 
settings and layer specific Curves adjustment layers. 

Cheers,

  ~DannyR~