Do you have questions or are you looking for best practices on integrating line of business applications with Microsoft SharePoint Products and Technologies, taking advantage of publishing and content oriented capabilities, or creating collaborative interactions around business processes? If you answered yes to any of these questions, I'd recommend reading the just published content, Developing SharePoint Applications, in the Patterns and Practices Developer Center.
This guidance will help developers and architects accelerate construction of advanced applications through both examples and documentation, ensures alignment with recommendations and best practices and compliments existing platform documentation.
Microsoft Office SharePoint Server Developer Center
Windows SharePoint Services 3.0 SDK
SharePoint Server 2007 SDK