Question: How toturn .h file +dll into some kind of .Net wrapper? or something like that? (no C\C++ sources just h files)

Answer: 
On Windows this kind of stuff can be recovered directly from the registry (regedit).

Search the web to find out the specific registry paths, like [this](http://www.ehow.com/how_6325458_configure-browser-using-regedit-xp.html).
According to Microsoft you should not use the registry directly.
See : <http://msdn.microsoft.com/en-us/library/windows/desktop/cc144154(v=vs.85).aspx>