I wrote my first SPS2003 .NET app today. This WebDAV Dog is learning new Sharepoint tricks, but step one is figuring out how in the heck to reference the Sharepoint Libraries in a VS.NET application.
First of all, this ain't mine. I found this newsgroup post of Jim McCusker titled Creating a Web Part - Step-by-step. Jim, whatever cool Sharepoint coding you're doing tonight, thanks, buddy! Here is Jim's post. Below is an excerpt on referencing the Sharepoint Services Libraries in VS.NET.
...2) Right click on the References folder in the Solution Explorer window and select Add Reference
...5) Browse to the file called Microsoft.SharePoint.dll which is typically located under the \Program Files\Common Files\Microsoft Shared\Web Server Extensions\60\ISAPI\ folder. [ex. \\cdpofb2\c$\Program Files\Common Files\Microsoft Shared\Web Server Extensions\60\ISAPI\Microsoft.SharePoint.dll]
The rest is in the Sharepoint SDK...