My experience for great Grayscale imaging is inline with Bobby H and quickseps, using L*a*b and/or Calculations.
Techamn,
Scott Kelby’s book is good, however, IMHO, the “best” channels book to date is Photoshop Channel Chops by Biedny, Monroy, and Moody (ISBN-1562057237). Still applicable even today with CS3 released! It took many months and a few bucks, but I finally sourced one a few years ago and have it signed by Bert himself. The Photoshop Channels Bookis a good investment and much easier to obtain then the PS Channel Chops tome. Now, real life seminars, I’d take Kelby over Monroy for “style of instruction” any day of the week; Kelby is just such an infectious, fully energized, over the top kind of instructor.