How can I get started making wads?

[DisgaeaxEtna]

I'm not completely sure about wad creation so I'll ask here. Is there some sort of tutorial or some site or even a topic that goes step by step about wad creation? The only thing I could think about in thought of wad creation is something similar to sprite creation. . Then again I'm not even completely sure that it's like that. So, No harm intended I just need a bit of help that's all. .

 

[D00D64]

http://wiki.srb2.org/wiki/Main_Page

Tutorials and references here. However, some tutorials are out of date, so things like Linedef types, texture names, thing types and so-on may have been changed.