John Scalzi's sequel to The Collapsing Empire, The Consuming Fire is coming out in the UK in October.
The Kindle edition of the paperback is available for pre-order, currently at £3.79
If you pre-order you get it for the lowest price it's available at between now and its release.
(NB There is a Kindle edition of the hardback, which releases two days before the paperback, but it's over £9!)