I'm looking for a good callmanager book for 5.0 or 5.1.. has anyone seen one? I've just seen 4.1 books.
Use the 5.x and 6.x SRND as a starting point. That's actually a good "book"...
Also use the Sytem Guide, Admin Guide, Feature Guide.
AFAIK there is no book available now and not coming soon (at least nothing on CiscoPress).
My experience with books: as soon as it's printed, it's old anyway... :-)