I just found out that Humble Bundle has a book bundle for Terry Pratchett’s Discworld. A 39 book bundle that is redeemed through Kobo.com.
Edit: Only available in the US.
https://www.humblebundle.com/books/terry-pratchetts-discworld-harpercollins-books
Not available in Aus either, and other Kobo bundles have been. Probably a publisher issue.