What experience do you have with OOP (Object Oriented Programming)? If you do not have any yet, buy some books about OOP concepts. That will be your biggest learning curve (by very, very far) compared to procedural programming. Note that I am not speaking about knowing how to use objects, but rather how to design and implement objects.
Otherwise, try ASP.NET Professional (used to be from Wrox Press, now maybe with APress). This will give you a good start about ASP.NET by itself.