Newbie Needs Help, Please!

Hi, Everyone,

This GIMP thinggy looks very nice, but first off, how do I get the
help files??  It's available online, I know, but ain't they supposed
to be part of the program??

Another thing...how do I create a simple .png image for purposes of
website opacity (like when I want to overlay a part of the screen)??
I'm totally new to the world of graphics software, BTW!

Last thing...how do I extract a tarball archive???  I downloaded
something called 7-Zip but all it ever does is make a copy of the
damned .tar file!!  WinZip claims not to be able to extract (unzip)
it, but it's able to see the individual files all right, and can call
up the browser to display them (they're all HTML; it's the "Grokking
the GIMP" manual I'm trying to extract)....


TIA!!!