Unit information is sent out by the Uni itself and not handled by OUA, so you will not be able to access anything through the OUA website. Print units are mailed out so if yours is print and you haven't received anything I'd give Curtin a call first thing Monday, although I've had unit information arrive during the first week (not with Curtin though). If the unit you're doing is fully online you may not get access information until the first day of the study period - Monday. In this case you should receive an email giving you all the relevant access information.
If you dont receive an email Monday morning, give Curtin a call and they'll be able to let you know whats happening.