Welcome to Australia! These days it's hard to go past the internet for information. Maybe more than you'll find in any book.

For buying Gold and Silver in Sydney it depends on what you're after. I do like KJC Bullion for semi-numismatic coins and have been to Jaggards a couple times though they are probably more focused on numismatics. Maybe Goldtrex if you want to try your luck in finding a bargain. I think I saw my first Krugerrrand there. Otherwise ABC Bullion is pretty big and had the best security of them all.