You can watch some of the classic matches from this year's Aussie Open for free on the eurosport website.

Go to http://www.eurosport.co.uk/tennis/mc_vid30284.shtml  

and scroll down the page to get to the list of tennis video clips and click "next".  Then you have a choice of watching Murray-Nadal, Sharapova-Williams, Roddick-Ancic and Williams-Peer.  All matches are in full !