psa
It's been surprisingly hard to find places to donate to Australian flood relief (MSF, Oxfam and Red Cross don't appear to do business with Australia), but there's a Queensland government donate site. Note that dollars is Australian dollars, but the current exchange rate is nearly 1:1.
ETA: Ha ha you can totally do Red Cross, it just has to be redcross.org.au.
ETA: Ha ha you can totally do Red Cross, it just has to be redcross.org.au.