First thing: you can't inject a managed DLL directly into another process and execute your code. You need a native (mostly written in C++) wrapper, which initializes the .net host and executes your code then (good explained at
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Furthermore I truely find tutorials for VB.net concerning DirectX (especially D3D). These are not containing things for gamehacking, of course, but only some "Getting started" things. But if you worked out how to handle with the D3D COM-object (explained in the tutorials), it isn't that hard to look in the documentation of microsoft (DirectX SDK August 2007 is the last one supporting managed DirectX/D3D).
I really think, that VB.net is a very comfortable language (with an easy syntax). But where is the difference between VB.net and C++ (native). With both languages you can make object orientated programming (OOP). But in vb.net you are forced to use the .net framework (you already know, that I don't like it :D ), while in C++ you can decide if you want to use it or not (native or CLI). Furthermore it's much easier in C++ to use inline ASM (if you need it) than in VB.net.
It's true that you can make many things in VB.net (mostly all things), but it's not a (in my opinion) good gamehacking language.