Where to buy
Where possible, I would encourage you to order the books from your local bookstore or public library.
All you need is the ISBN code:
The paperbacks can otherwise be purchased online from Wordery, who offer free delivery worldwide. (Though please note that, depending on where you live in the world, you may have to pay customs duty and/or VAT.)
In Svalbard, The Other Mermaid is on sale at the North Pole Expedition Museum in Longyearbyen.
In Denmark, the Kingdom of Clockwork paperbacks are on sale in the gift shop of the Round Tower of Copenhagen and the bookshop Fantask, who also have a mail order service.
Currently, these are also the only places where the box set of the Kingdom of Clockwork trilogy is available (see illustration above), but write to me at firstname.lastname@example.org if you have problems obtaining it.
Available from most audiobook distributors, including Mofibo, Audible, etc. :