When you buy one of these how do you get it hooked up with Amazon so that the books will be delivered to the Kindle?
If I reading the description correctly, there is no backlight. That means I need a light on just like a regular book in bed or in a dim room? I understand they say it’s easier on your eyes but it won’t stop the light from bothering sleepers or tv watchers like a lit screen would 
Correct, no backlight. Kindles didn’t start to include a backlight until the Paperwhite was introduced.
For non-backlit Kindles you can typically find a protective case with a flip-out booklight built in: link
From the Specs: “Amazon Kindle 5th Generation - Sauza (2012)”
From the In the Box section: “Kindle (4th Generation) Wi-Fi E-Reader”
Is this a 4th or 5th gen Kindle?
It’s a 5th generation. Thanks for pointing out the mistake!
Does this have a speaker, i.e. can you listen to audible books?
No, it does not. The Kindle Touch does.
What does it mean includes ads? Do these pop up when you reading like spam ads on a website?
You see them on start-up and if the device goes to sleep, I believe. Everything I’ve heard from wooters is that it’s non-intrusive. You can subscribe to turn them off though.
Can I use this to borrow public library books via Overdrive?
Yes. Works well by integrating with Amazon
These Kindles have physical buttons on the side which make flipping pages convenient.
My wife’s Kindle Paperwhite is bright enough to light up our bedroom at night. It doesn’t bother me, but if light in a concern, this Kindle with a small booklight might be better since the light shines down on the ereader rather than radiating light upward and outward.
That is correct. It is not backlit and you will need a light source to read it.
Actually, I just unsubscribed from their ads and there’s a $15 charge. Had I known that when I bought it, I would have bought a Nook.
Yeah, there are a lot of cases with lights built in on Amazon or other vendors that will solve your light problem.
Here’s one:
https://www.amazon.com/Verbatim-Folio-Kindle-Bronze-98081/dp/B00B6OX6P0/
I do like the paperwhite with the backlit screen, but I only use it late at night. Otherwise, I’m reading without it, and the tech used on the Kindles is great for eye strain.
The ads are very unobtrusive. They are basically the “screensaver” when you put the Kindle to sleep. Once you swipe to go to the main screen, they are gone. Not annoying at all, and well worth it to get a device for even cheaper.
Is that $15 charge once or a recurring thing?
I believe it’s a one-time payment.
You only see the ads on the screen saver and on start-up. From what I’ve heard from wooters, it’s not intrusive at all.