I haven't tried it personally, but I believe that you should be able to add one of the Leap Motion C# assemblies as a reference to your VB.net project. The SDK includes an libraries for .Net 3.5, 4.0, There are also community created libraries for .Net 4.5 compiled by Mark Rowe.
You also need the Leap Motion native libraries, LeapCSharp.dll and Leap.dll (on Windows) in the same directory as the LeapCSharp.NETn.n.dll.