I am a c#/c++/html/css/javascript programmer with experience coding/compiling/running on my machine only. I have recently got my hands on another computer and installed windows server 2012 64bit. I want to host a website on this with asp.net and run web services and SQL server. Basically I want to turn this into my web coding box for testing and learning.

I have no idea what I'm getting into or where to start. I installed the Server OS but now I have no idea what I'm doing. How do I even make a web page or web app/service?

I really need a book or some kind of intro to using a server for programming but my googling is not coming up with a good result. Does anyone know a book or other resource for someone who knows code but never got into the networking side of things? I don't want to get bogged down in tons of theory I just want to start writing code using this server.

Good for you! The Microsoft web development environment is not as heavily documented online as the Linux-like environment used by Google, Facebook, and the likes, but it's still quite capable.

MSDN has some tutorials and get started guides. For example: https://msdn.microsoft.com/en-us/library/gg615484%28v=vs.88%29.aspx?f=255&MSPPError=-2147217396
There are also ASP.NET specific tutorials, some of which are linked from: http://www.asp.net/get-started
Finally, the terrible-but-sometimes-convenient site known as W3Schools will also get you started: http://www.w3schools.com/aspnet/

Beware which bits of ASP.NET are Microsoft-specific, though, relying on Internet Explorer or client-side .NET framework.

If I were to start a new web app, I'd probably instead use React, and either Node.js, or Apache, as the web server, and likely Postgres or MySQL for the database server. Those systems are more like "the mainstream of web development" -- but that's because I live in the silicon valley. If you want to develop the way many "normal" companies and enterprises develop, Internet Information Server, ASP.NET, and MS SQL Server are a fine way to go.

Good luck, and if you get stuck on a particular thing, please ask a specific question!
(Like "I'm trying to do <exact thing X> but I don't understand the documentation at <site Y> -- I get an error saying "the W is doing Q" -- what does that mean?")

To get you started on the server itself:

You need to install a web server "role" in order to get access to IIS. IIS is Microsoft's web server backend, and the reference platform for asp.net.

As for the sql server, just install your preferred edition on the box. Express will work fine.