How can I tell what products are in stock?

When browsing product categories or product search results, you'll see 'product tiles' each with a button at the bottom, like this;

The three buttons mean the following:

• "CHOOSE OPTIONS" means that the product is in stock, but there are options or product variations that can be chosen before adding the product to your cart.
• "ADD TO CART" means that the product is in stock, and can be added to your shopping cart in one click by pressing the button.
• "NOTIFY ME" means that the product is out of stock, and by clicking on the button you can enter your email address on the product page to be notified when it is available.