Here is a list of links that you may find useful, starting with mints from around the world, then dealers of Australian coins, followed by reference and collectors sites, forums and finally books.
If you find a dead link or would like your site to be included or removed please send an email.
The lists are in no particular order.
Mints
Australia
The Americas
United Kingdom
Asia
Europe
Africa
Australian Coin Dealers
Auction Sites
Ebay is the only auction site to have no responsibility for its listings, buyer
beware.
Reference Material
A dedicated UK site with large resources on the history, making and availability
of sovereigns, with many for sale if the Pound to Aussie peso conversion rate
dosn't scare you.
Jon Saxton's site, (an Aussie living in the US), a dedicated collector of
pre-decimal coinage, with an emphasis on dies and varieties.
The on-line version of the Coin-Web CD, listing almost all of Australia's coins
and banknotes since the First Settlement, with pictures and information.
Your guide to British coins
Other Sites by Collectors
A great resource for putting your collection on-line and allowing others to see your
coins.
Has not been updated since opening retail premises in May 2005