I just recently started switching.
I am quite experienced in ASP classic and I had been writing vb.net apps more in the past then asp.net, but now at work they decided any new stuff my team does will be in asp.net using C#.
I've done some VB asp.net work previously, there are somethings I have found challenging but I am sure if you were to move from VBScript ASP classic to vb.net ASP.net it wouldn't be as difficult as vbscript to C#.
However, I am starting to like the C# syntax better. You can kinda think of it as VB with Java syntax. Once you start to get the hang of it, like most things, gets easier.
I've had to do some pretty crazy things like maintain the same session states in ColdFusion, ASP, and ASP.net for the same website. It took some creative thinking. I got some asp.net links at work, I'll post them on monday.
Lastly, remember google, it is your friend....