If you always wanted to create your own runescape private server, then these are good news: It is posible! And it is quite simple. In this tutorial, you will learn how.

Getting a Source and Client

Firs of all, you need to get a Server Source, which is a pre-made server that your server will be based on. I personally recommend TestScape because it is very versatile.
Then, you need to get a Client, which will let you get on your server. MoparScape is a great client, but there's a variety of other clients just as good, if not better. When you get more experienced, you will be able to make your own client, that can even be a WebClient!
There's a good list of Sources and clients here on Moparscape forums.

Configuring your Server

Next, you need to configure your server so people can get in. To do that you need to get Java JDK.
You can download JDK from Sun.
After installing it, enter the directory where you installed it and search for a file called javac.exe. Copy to clipboard the directory where the file is located.
Now, unconpress the Source you downloaded and open compile.exe and runserver.exe with Wordpad or any other software. Change the directory to the one you have just copied to clipboard in both files.
*Note: If you get an error stating that "javac.exe isn't recognized as a command" or something similar, you must add a variable and system variable. These steps are harmless; don't worry.
1. Start>Control Panel>System>Advanced>Environmental Variables. In user variables you have to add javac. Click on new, name it javac and put in the directory on the bottom. For example, on my computer mine is like this C:\Program Files\Java\jdk1.6.0_07\bin\javac. Then Click OK.
2. Now for System Variables click on new and name it javac. Then put in directory of the folder containing javac like this(may vary on your own directory):
C:\Program Files\Java\jdk1.6.0_07\bin. Now hit OK and OK again. Click Apply and OK. Run the Program and it should work.
IMPORTANT: If you dont want to modify the files, theres an easier way! Get the perfect compiler, that will do all of the work for you located here.

Publishing your Server

The easiest way to publish your server is to get Hamachi (you can download it here). Install it; enter Hamachi and choose the option Create New Network. Enter any name and password.
When someone wants to enter your server he/she will have to download Hamachi and join your Network (you will have to provide the password).
At the top of Hamachi, you will see theres an IP. That's your IP, and we will use it to connect to your server.

Enter to Your Server!

Now everything is ready. Go to the Source and run Compile.exe. A black screen will appear telling you their were no errors. Now, run Runserver.exe and leave it open. As long as that file is running, your server is online. We are very close to finishing this process.

Enter the Client you downloaded. Wait until it loads, first time will take quite a while. Now, enter with any username and password and in IP write the IP we had seen before in Hamachi.
If everything goes right, you will appear somewhere in the World of RuneScape, in your own server!

Congratulations on creating your Own Runescape Private Server!