PLC Books/Documents

Hello. I want to learn PLC Programming. Which books/document do you advise for beginner ?

Got any software background already? This might be the way to go:

I was trying to find what book, if any, they use, am not seeing one.
Or maybe this, looks free?

Never done any PLC myself, seems like a variation on state machine logic to me.

mrtamer:
Hello. I want to learn PLC Programming. Which books/document do you advise for beginner ?

See also the site for those just starting out in PLCs (Programmable Logic controllers) , see the recommended PLC learning path at http://plc-training.org