There are a few universities in Australia offering distance learning courses in human factors (I believe they are available to people living overseas).
I think Griffith Uni has an undergraduate module in Aviation Human Factors, and Aviation Biology by DL.
UNSW has a postgraduate Human Factors course by DL.
There are others too I think.
I do not recommend you go straight into postgraduate level human factors course, and be warned that it is mostly psychology and designed more for those with academic interests than those seeking knowledge for the purpose of "operational level" knowledge.
PM me if you want to know more.