Keith's website (http://www.famie.com/h_index.htm) has an informative section on Australian slang. My personal favorites are:

Nick the Bludger (Bludger: Lazy person, layabout)
Kel the Digger (Digger: A soldier)
Earbash Kimmi (Earbash: Non-stop chatter)
No-hoper Debb (No-hoper: Loser)
Jeff the Whinger (Whinge: Complain incessantly)
Roger the Wowser (Wowser: Straight-laced person, puritan)
Jerry the Swagman (Swagman: Tramp)
Stickybeak Tina (Stickybeak: Nosy person)

AUSTRALIAN SLANG

Arvo: Afternoon.
Avos: Avocados.
Avago You Mug: Shout of encouragement to a sportsman not performing to his best
Banana bender: A Queenslander.
Barbie: Barbecue, as in "I'll throw some shrimp and chook on the barbie."
Bash: Party. Also "fancy turns".
Bonzer: Pronounced "bonsa" - grouse, great, excellent.
Bloke: Man, guy.
Bludger: Lazy person, layabout.
Bluey: (also known as Blue) Slang for any bloke with red hair, and also known to describe the Australian Cattle Dog.
Bonnet: Hood of a car.
Boomer: A large male kangaroo, as Rolf Harris sings, "Six white boomers, snow white boomers on Santa's Australian run...".
Boot: Trunk of a car.
Bottle shop: Liquor shop.
Box of blowflies: Ugly, as in "that's as ugly as a box of blowflies!" And that's pretty ugly!
Buckley's Chance: No chance at all.
Bung: To put or place. E.g bung another snag on the barbie
Bunyip: A mythical bush spirit, Australia's bigfoot. Probably just a hairy surfie!
Capsicums: Green or red bell peppers.
Carpetbagger steak: Beef stuffed with oysters.
Chemist shop: Drug store.
Chew the Fat: To talk, engage in pleasant conversation, to have a chinwag.
Chook: Chicken. Often served barbecued at fancy turns. If your hostess is befuddled and/or overcome by trying to do too many things at once, one might say she was "running around like a chook with its head cut-off!"
Cockie: Farmer.
Cockroach: Someone from New South Wales
Crook: Sick, or badly made.
Crow eater: A South Australian.
Dag: A funny person, nerd, goof, loser.
Digger: A soldier.
Dilly-bag: Food bag.
Ding bat: Fool.
Dinky-di: The real thing.
Donk: Car or boat engine.
Donkey's years: Ages.
Drop-in: To steal a surfer's wave. This is a serious crime in Surfer's Paradise.
Earbash: Non-stop chatter.
Esky: Portable icebox or cooler - it's always a good idea to have one in the boot stocked with some cold ones just in case the party's bar runs dry.
Fair Dinkum: Kosher, the real thing - as in "Fair Dinkum Aussie" (true blue Aussie original). Often used by itself as a rhetorical question to express astonishment verging on disbelief ... "Fair Dinkum, mate?" (you've got to be kidding, haven't you?)
Fair go: A good chance
Footpath: Sidewalk.
Footy: Rugby League
Flyer: female kangaroo
Galah: Noisy fool, named after the bird of the same name.
Game: Brave.
G'arn: Go on, you're kidding!
G'day: Universal greeting, used anytime day or night, but never as a farewell. Pronounced "gud-eye", usually followed by "mate" (mite) or a typically strung-together "howyagoinallright"(= how are you today, feeling pretty good?)
Give it a burl: Try it.
Good as gold: Great!
Good oil: Useful information, a good idea.
Good Onya: Omnipresent term of approval, sometimes ironic, offering various degrees of heartfelt congratulations depending on inflection. Indispensible during Aussie smalltalk - substitute "really, oh yeh, aha, etc."
Grizzle: To complain.
Grouse: Rhymes with "house" - means outstanding, tremendous. Can be applied
universally to all things
social ... "grouse birds (women), grouse band, in fact, grouse bloody gay and hearty (great party!)"
Have a yarn: To talk to someone.
Hit your kick: Open your wallet.
Hooroo: Pronounced "who-ru"... means "see ya later", make sure you don't say g'day when meaning goodbye - it's a dead giveaway you're not a true blue Aussie.
Hotel: Often just a pub.
Icy pole: Popsicle.
Jackaroo: A male ranch hand.
Jillaroo: A female ranch hand.
Joey: Baby kangaroo.
Journo: Journalist.
Jumbuck: Sheep.
Jumper: Sweater.
Knock: To criticise.
Lemon squash: Lemonade.
Lob-in: Drop in to see someone.
Lollies: Sweets.
Lolly water: Soft drink.
Never Never: Distant outback.
No-hoper: A fool, loser
Offsider: An assistant.
O.S.: Overseas, as in "she's gone O.S."
Oz: Australia; God's country
Pines: Pineapples.
Pommie or pom: An Englishman.
Rafferty's rules: Chaos, disorder.
Reckon: Think, as in "Your shout or mine? What' ya reckon?".
Ridgy-didge: Original, genuine.
Right: Okay, as in "she'll be right, mate."
Ring, tingle: Phone someone up, as in "I'll give him a ring."
Ripper: Pronounced "rippa" means beaut, tippy-tops, grouse
Rubbish: To knock something.
Sandgroper: A Western Australian.
Shark biscuit: New surfers, grommets on boogie boards. Tres uncool!
Sheila: A woman
She'll be right: No problem, don't worry, mate.
Shootin' through: Leave, take off.
Smoko: Smoke or coffee break.
Snag: A sausage.
Sook: Someone who complains a lot
Spit The Dummie: A "dummie" is Australian for a child's pacifier. Lose your cool
Stickybeak: Nosy person.
Stone the crows: An exclamation of surprise.
Strewth: Pronounced "sta-ruth" ... general exclamation of disbelief or shock.
Strine: Australian slang, from "Aus-strine", the way Aussies say Australian.
Swagman: Itinerant farm worker, tramp
Taswegian: A resident of Tasmania.
Tee-up: To set up an appointment.
Tomato sauce: Ketchup.
Too right: Definitely!
True blue: Honest, straight.
The Lucky Country: Why, Australia, of course.
Tucker: Food.
Vegemite: A dark brown, gooey, salty vegetable yeast extract. It's what makes Aussies strong.
Wally: Idiot
Whinge: Rhymes with "hinge" as in door! Means to complain incessantly
Woopwoop: in the boonies, nowhere.
Wowser: Straight-laced person, prude, puritan, spoilsport.
Yabber: Talk.
Yobbo: An uncouth person