Just visit the website homepage and choose between the various products available - make sure to scroll down to browse through all the available categories of items.
You can shop for physical products here.
Once you see a product you're interested in, just click on it to read more details and then use the “Add to Cart” button to select the ones you would like to purchase. Once you are done shopping, just select your Cart on the right side of the main menu and click “Buy” to proceed to the checkout page and place your order.