You need one to download it, but other than that, probably not.
Yes, It needs internet to download and share models but it can be used without an internet connection.
Yes.
You can install it, but to download the installer... Yes, you do.
Both the Pro and Standard versions of Google's SketchUp can be used on a Mac. Google provides many resources to help a user learn about SketchUp (See links below) .
No, you dont have to buy Google Sketchup, but you will have to pay if you want the better Sketchup Pro edition.
use the pull tool.
Sketchup Pro versions with limited accessories are available for free through Google itself at the Sketchup Pro site. In addition, full Pro versions are available for school and educational use.
Google Sketchup site provides a tutorial for it. See the related links.
go to google and type in google sketchup download google sketchup and make a custom tron
google sketchup pCon.planner
Yes
yes
you use google sketchup and export it as a .b3d format file