The only way to get a signed copy is backing a tier that has a bookplate. That will be signed by all the artists of this series.
As a company owned and operated by creators we give a majority of the profits from the books to the creators. The amount left over has to be used for the tens of thousands of dollars in shipping, supplies, labor, and taxes.
Sorry, we can't let you choose which book to you get during the Kickstarter as we're trying to fund the publication of ALL the books.
Don't see the answer to your question? Ask the project creator directly.