Unlike many academics, I think textbooks are very important.
They are useful for students; but more than this they help define and codify fields of inquiry – they provide a snap shot of the state of the art.
I have been involved with three textbooks. I cannot reproduce them of course – they are too large. But some of them can be accessed on web sites in quite a lot of detail.
My three key text books are:
Sociology: The Basics (2010)
Sociology: A Global Introduction (5th edition: 2011)
Criminology ( 2008: 2nd edition) with Carrabine and others.