Prism now has samples in VB which you can download here.
This article gives an overview - Prism allows you to develop in either WPF or Silverlight (or do linked projects which provide UIs in both WPF and Silverlight with some code) - the article mentions Silverlight but you can ignore that and still get an overview of Prism/CAG.
On the other hand, there are C# to VB translators out there - have you tried them? I made the switch from VB to C# a while back when I found that all of the sample code for the areas I was interested in were in C#. I'm glad I switched. From your PoV, it probably looks harder to read but once you're into it, it's so much easier because there's so much less excess code to clutter up the screen.