Hi Benderza,
Wrox has an awesome book for ASP.Net 2.0 Programming.
So does Microsoft with their publications, although they are a bit more framework specific.
Also consider this book which I haven't read but I heard it takes the cake. (I would get this one if I had to do it all over again, the Wrox book was great but was a hassle sometimes)
Your migration should go relatively easy once you grasp the fundamentals of ASP.Net 2.0. You will also find the code you write will be significantly less...2.0 is a Rolls-Royce compared to anything prior, and especially its php counterpart if you are .net saavy. I'd estimate it'll probably take you 2 weeks to a month to get the hang of it, providing you're already proficient with VB.Net.
Jon