Thank to sshi, visibleprocrastinations, Sue, Siobhan for supplying information on Alzheimer's charities from around the world.
You can give directly to either of these two Australian organisations. The links will take you straight to their donation page.
Can a French speaker have a look at the France Alzheimer's site and let me know a URL that goes straight to a donation page. France Alzheimer's Donation Page (Thanks Joanna).
You can probably give to Alzheimer’s Canada but their site is down at the moment.
From K`shandra
A recommendation for those who use the online donation page at Alzheimer's Association (USA) - use the Tribute link, and note that your contribution is in honor of Match It For Pratchett. It's not perfect (there's only room to note one honor/memorial, so you can't mention that AND a family member or friend), but it would be nice to see how many contributions the other organizations outside the UK receive.
I've updated the Guide to Giving with the new direct donation links and there is a new page for a list ofAlzheimer's Groups from around the world.

http://www.francealzheimer.com/pages/agir/don-enligne.php
Does that help? It's the donate page, although it's still in French.
Posted by: Joanna | March 17, 2008 at 09:05 PM
Alzheimer's Canada is down, but most Canadians, if they google "Alzheimer's" + the name of their city or the nearest city or their county, will find a local chapter able to take online donations.
I gave at
http://alzheimerott.org/, for example.
Posted by: Marna Nightingale | March 18, 2008 at 04:49 AM
Also, the donations page for the Alzheimer's Society of Ireland is at http://www.mycharity.ie/donate_charityIndex.php?charityID=6
Could you update your Guide to Giving with this information, please? The Society's website is http://www.alzheimers.ie and they also have a fundraising Tea Day on the 1st of May with a website at http://www.teaday.ie
Posted by: sshi | March 18, 2008 at 03:20 PM
Okay, this doesn't seem to have gone through the first time. For the Netherlands, this is the link I've seen used: http://www.alzheimer-nederland.nl/content.jsp?objectid=118
which leads you straight to a bunch of donation options.
Posted by: Kimberley Verburg | April 02, 2008 at 09:42 PM