The user manual contains detailed information on every single option in Logic Gui.
It is designed to be printable - if needed!
The user manual does have a hyperlinked index to all topics. The topics itself are organized in the order of the Logic Gui menus.
Use also the search functionality in Acrobat, it is nice and finds easily all related text passages of a certain keyword. This is important, because some functionality you are looking for are connected to several topics.
You can download the user user manual also as PDF from the Download section.