What about a digital photo frame and then he can enjoy pictures? Or you could go online and get him tickets to a big Aussie sporting fixture to get him started on aussie sports?
also you could burn a cd of memorable music - aussie music is a bit...crap different.
Choose songs that evoke memories. You could also put podcasts from the BBC on so he can listen to sports coverage if he wants to hear a british voice.
Get him a Slingbox. You plug it into your telly at home and he plugs his computer into his telly in Aus and he can watch terrestrial UK TV. We are getting one for Christmas and are hugely excited!
There are big fines for bringing food into the country so no point loading him up with biscuits and crisps to take with him. Tea leaves are a definite no and he will get fined if the package is opened.
My in-laws bought ours at Curry's or Dixon's - apparently they have them in stock but nobody who works there has the faintest idea what they're for, so you'll have to ask for it by name and set it up yourself.