For fans living outside Korea, these websites ship internationally, except for coolktime which is only for those living in Singapore.
You will need a credit/debit card and an account for most of these websites, except for Coolktime.
(For coolktime, go to the website linked above, scroll down and click:
Then, scroll down and type "Alexander" into the search box:
Click on Alexander's I Just, follow the instructions stated and send an email to coolktime, they will reply you with the date of collection and where to collect your album. Payment will be made upon collection, so do bring your payment in cash.