Macmillan >>>>> Heinemann. It is, however, out of print, but available on a CD which you would have to track down somehow (my school had it on the network, so I copied it onto a USB and brought it home).
Alternatively, your school library may have a copy of this "Living Lingo" book for you to borrow, or the State Library often has VCE textbooks which you would be able to photocopy relevant sections of*
As for websites, newspaper databases are brilliant for finding current examples and quotes if you want them. e.g. type in "jargon" when you study it, and you'll get articles about Kevin Rudd's jargon, etc. Wikipedia was also a useful resource (there are articles on pretty much everything you study).
* it seems new, though, so good luck finding a copy