If you are looking to get up and running quickly with Windows Forms applications, check out the Smart Client - Composite UI Application Block
that has recently been released. Here is an overview...
"How can you build complex user interfaces that take advantage of the power of the Microsoft Windows desktop, interact with multiple back-end systems, are easily deployed and configured, provide a rich user experience, use complex data manipulation mechanisms that enhance user interface responsiveness and yet are developed in a predictable and agile way? How can you architect an end-user application so it can be easily updated and maintained or in environments where multiple development teams can collaborate over time in the most effective way?
The Composite UI Application Block is designed to help you build these complex, enterprise-ready Windows Forms–based solutions. It provides a proven architecture and implementation that helps you to build applications using the common patterns found in line-of-business front-end applications."