Where can I find more information about building N- tier applications?
At the time this book was published, there were no good N-tier .NET development books. However, several exist for other platforms including COM and Visual Basic 6.0. One good book on the topic is Building N-Tier Applications with COM and Visual Basic(r) 6.0 by Ash Rofail and Tony Martin, published by John Wiley & Sons. If you're familiar with the technology used, the N-tier concepts will be easy to follow.