This site hosts lessons for the WC3 programming language VJass. In order to program this, you will need some
form of JASSHelper. You can install SharpCraft or NewGen World Editor to get these.
Lesson Directory: links to lessons
JASSHelper Documentation: contains documentation for language features
JASS Manual: contains an API browser to find any native/function/etc.
SharpCraft Download: I use SharpCraft, but you can use NewGen if you get it working on your patch.
WC3 1.28.5 Download: Download the package WarCraft III 1.28.5