Quick Maccas Questions

Hello - Yank here... I keep seeing references to "Maccas" as an reference to Australian coin values. I did a search on Amazon to no avail.

Also - I've read that the " Red Book" here in the States is considered to overvalue coins. Is the same true of Maccas? And any ideas what search terms I could use to find this book if I'd like to buy one? Or should I just post pics here unendlessly and ask? ;)

:P

Thanks for your help!

AND - as there are likely Aussies reading this, congrats to your man Webber on the GP over the weekend! That's awesome! =)

Cheers!