Rigid plastic containers can be put in your yellow-lid recycling bin or taken to any Waste and Recycling Centre for free (for loads under 1m3). Empty contents, but no need to rinse.
Rigid plastic containers include items like biscuit trays, fruit punnets, ice cream containers, butter and margarine containers and takeaway containers.
If you are unsure, check the packaging for the Australasian Recycling Label.