The 7 is currently FREE on Kindle through December 1 (tomorrow). It's normally 99 cents, although it's always free to borrow for Prime members. Get it on Amazon.
Darwood & Smitty (and the Multi-World Agenda) is also discounted. Normally $2.99, you can now pick it up on Kindle for just 99 cents through December 6. It's also always free to borrow for Prime members. Get it on Amazon.
Both books are always free on Kindle if you buy the paperback version through Amazon as well.