Can you purchase written books?

@E45Dodge Do you mean how to open a retail store with the Get to Work expansion?

There's an icon added on the far right if you have Get to Work (or Cats & Dogs, which adds the ability to own a vet clinic). Open this, make sure you're in the retail tab, and click "Buy a Retail"

Choose a lot you can afford - it can be empty, but you won't be allowed to open until you have at least a cash register and that cash register will need a counter to sit on. Transfer funds into your business account and if they're not already on the lot, buy a counter and cash register.

You can now sell pretty much anything by placing it on the lot and marking it for sale. If you have an author who's written some books, they could bring their books here instead of mailing them off to a publisher. Then you open your shop. You can even get copies of your book by restocking after it sells. You'll need to use the sales social interactions with customers to encourage them to buy, ring them up when they're ready, and clean counter and table tops when they get dirty.

Hey! So I've been working on this recently!

The way that I've decided to do it is

• Sim Writes Book
• Create Copy of Book - Placed in a storage box until I got a few to sell!
• Publish Original at the mailbox(however you choose to publish for money or story is up to you!
• Purchase a retail store/lot(I made a coffeeshop/bookstore!)
• Get copies of written books out of the storage box, place in sims inventory
• Travel to Retail store!
• Drag and place written books on displays - Tag as "For Sale" from register
  
  Now sims from other households can purchase books written by this sim!
  
  Note: Since For Rent, there is a current bug with sim-owned retail lots. To allow other households to visit the retail store and purchase books, you must first open the retail store on the owner/household.
  
  

You can't purchase them but your can create a copy.

In the cheat menu (ctrl+shift+C) 

cheat code (TestingCheats on)

Once you have the cheat code take the written book out of inventory. Hold shift and click the book and you will get the option to create a copy. You can then sell the original but, retain a copy of the book for your sim to own. Copies cannot be published through the mailbox, only original copies.

I am unsure of a way to get copies of books you have already sold, but I would love to get one. So far I don't know of a mod to recover those books either. But any books you have from now on will be available to you.

@Vandipitty I'm sorry you can't sell them.

However, if you need other families to have the book, as long as you have Seasons, you can give out your copies as gifts. That's how I populate other households with the written books.

With the Life and Death expansion being out now you can probably also add the books to the author's will so when the author dies the books will get inherited by whoever was marked as recipient in the will? So that would be an alternative way to spread books around to other households because the Sims who you mark as recipients don't have to be from same family.