You would use this overload of the Graphics.DrawImage method. This overload allows you to specify the location inside the specified image that you want to draw.

You mentioned:
X 32-64 and Y 0-32 of the tileset
This would translate into a Rectangle object that looks like this:
Code:
Dim sourceRect = New Rectangle(32, 0, 32, 32)
Take a look at the example in the link I provided.