Microsoft CRM User’s Guide
There is a new manual out from Microsoft. Although it misses the “why” and “when” of CRM, it is still a good read (and a good place to get content to put into your own manual). My view is the docs Microsoft makes do not have enough pictures in them. So if you use any content, you may want to take “actual CRM” screenshots so the user’s see their own data, and can really understand “where” the buttons are located on the screen.