I'd wager most coding languages are described in their website docs rather than in physical books long before they reach libraries. Only the most popular languages get a full write up more than a few times and then you've got to compete against shelf space already occupied by long useful books. While library organizations orgs have our can get most books, your have to know what you were looking for in advance.
Yes and No. Every library is different. A university library may be better stocked, but my local library's computer section is mostly old books on outlook, Excel, and Photoshop. There are some coding books, but they're mostly old books on VB and the like that might be difficult for someone new to programming to setup. The topics on loops and branching and variables are probably all relevant, but it's harder to learn just by paper.
Our local library gets books only slightly slower than what I can get ordered online. From the time I ask for a book, they often have it on the shelf within a few days, with an automatic reservation for me sent by SMS for pickup at the local branch just outside the door. Of course this is the socialist country of Sweden and we love our libraries... :-)
Last time I got a ZX-spectrum coding book that a friend on a forum wrote. Before that some obscure manga comic book. That one took a few months because they had a hard time to find it, it was long out of print.
They are very open to suggestions even of odd books and very curious librarians, both young and old.
Here in the US, you can use interlibrary loan to get nearly any book from a public or university library. Worldcat [0] is a great resource for finding books in other libraries that can be sent to you free through ILL.
Mine has a place where we can make suggestions, but unless it is a university library where people donate money (Ex: Texas A&M) it might not have a high chance.
I never made the claim that you needed to learn the newest language. Some of the books competing for shelf space are great, long useful coding books. The section in most libraries for coding though is small.
I also never said you couldn't text yourself programming by going to the library, but most of the people who would go to the library to learn coding don't have home computers themselves, I'd wager, and need to use online IDEs which would mean having access to the internet with more up to date resources typically than what's available on the shelves.
In another comment on this topic I brought up that I personally use a blended approach of books for the why's and online for the how's. There's a ton of great coding books out there. Many unfortunately don't make it into library collections and the ones that do typically require either ordering via a hold or just buying outright beggar the library doesn't have it. I'm a huge library lover, you won't find me cheering for their demise.
Sadly, the website documentation for most languages is pretty terrible. Independent authors can take the time to write much more comprehensive educational books that go beyond just a simple language spec and a Github link.
Because there's no site (that I know of) that organizes books this way so you really can't browse related titles like you used to be able to. In the library shelves, you might find books which were related to what you searched -- even though their titles might not make that obvious.
All library catalogs have a browse function. You can see which books are shelved next to each other, although it is a linear display and you can't just "walk" to the next shelves.
Why?