When you take Google Nexus 7 out of box, there is only a quick start guide and a quasi-manual file. If you really need to learn how to use the tablet, a manual is the best thing. I have bought some N7 manuals, but it is disappointed that they are missing important information and also wihout up-to-date.
After making searching, I find that "Nexus 7 For Dummies book (Google Tablet) [Paperback] by Dan Gookin" from Amazon is what I am looking for. It is very helpful when you drive yourself nutty trying to figure out function on your own.
The book includes the 5 page Chapter 20 with tutorials, such as setup steps, typing and apps management tips, advice and etc. If you don't familiar with android devices, recommend purchasing it.