Following this up, I went and bought an OBD2 reader but it didn't work at all with my Subaru Outback. Can anyone recommend me an OBD2 reader that will work? (Prefer one from eBay or dealextreme as they will usually ship to Australia).
Previous posts from fellow Aussies and me (amongst others) suggests that off the shelf eBay readers don't work with out model cars, not being OBD2. I've had similar problems, ended up getting professionally read, then got onto Freessm. Check for Freessm, posts by Stig.