Immigration Nation by the SBS Network is a frequently used source for this website. On the site one can primarily find the three episodes of the documentary series but also a variety of related material, such as the overview documents attached to every major topic as you go through the episodes. Further, the site offers you an interactive tour of migrant contributions to Australia and is worth a look.
The final video displayed is a recording of the Sydney Maritime Museum's light show in 2014. The companion site also offers numerous additional material such as a break down of the scenes and personal migration stories.
Tim Soutphommasane's 'Mongrel Nation' is an interesting audio presentation about Australia's immigration history that discusses numerous current and historical features. It contains several guest speakers discussing changes and personal stories.