ninjaneer 1 Junior Poster in Training

I've been googling this topic for a while, but I haven't found a very clear tutorial.

I have created a GUI in C# (it's so easy!) and now I want to implement a C++ backend that I've got that is already created (also the C++ backend uses Microsoft Foundation Classes like cWinThread). I've read a lot about 'creating a managed DLL' and wrapping the C++ code... but I can't find any good tutorials, any of you C#ers have any good ones?