Many Bunnings stores offer timber cutting. On the Bunnings website, make sure you have selected your nearest store, then click on the name of your store on the top left of the screen. This will take you to your store's information page, which includes details on what services they offer. For timber cutting, I would just recommend that you try to visit at a quiet time (not weekends or public holidays).
Hope that helps. Let me also extend a very warm welcome to the Bunnings Workshop community. It's great to have you join us and we look forward to reading about all your projects and plans for around the house and garden. We're confident you will get plenty of helpful information, advice and inspiration from our clever and creative members, so please feel free to post anytime.