You can do international with your site, however it poses some issues with freight and supplier fulfillment. Currently there are no WD's in the USA that accept electronic International orders (excluding APO/FPO). If you are ok with this, the steps to configure your site to accept International orders (INTL) are as follows.
1) Go to your control panel
2) Go to store settings in the Administration section
3) Click 'edit store settings'
4) Scroll to the INTL field, and check it on, click save and exit
5) From the Control Panel click the link in the Misc. section titled, 'check store files for basic configuration'
The rate will be calculated from your store's zip code (this is modified in the 'store settings from above). The rates quoted are UPS Worldwide Express. They should match exactly the UPS website that anyone can use.
