iHerb - I love iHerb, they have so many great products that we don't have access to here and they're so cheap! I purchase Real Techniques, Physician's Formula, Eco Tools, Palmer's, Deep Steep and Korean beauty to name a few.
Shipping through DHL is fast and fully trackable, shipping through Australia Post is slower but free. If you haven't shopped at iHerb before, what are you waiting for? Code YUF175 will get you a discount off your first order.
ASOS - ASOS is great for buying products that have yet to be released or won't be released in Australia. I purchase Rimmel and Bourjois from them if I can't wait until they're released here. They also stock Pixi Beauty and some Carmex products we don't have here. Shipping is free when you spend over $40 and they regularly release discount codes so you can score 10 to 20% off.
Look Fantastic - Free worldwide shipping, a great range of brands and wonderful customer service make Look Fantastic a store I purchase from over and over again. I have products from Pixi and First Aid Beauty on my wishlist for my next order.
An honourable mention goes to Beautylish. I placed my first order with them a few weeks ago and was really happy with their service and the shipping speed. Shipping is free if you spend over $50 US. I'm already planning my next order.
What are your favourite international stores?