Microsoft has put up 101 Sharepoint 2010 code samples on the Microsoft Office Developer Center. The samples cover all sorts of tasks for working with lists and libraries in Sharepoint, also samples for BCS. Most samples are available in both c# and VB.
You can find all the samples here http://code.msdn.microsoft.com/site/search?f%5B0%5D.Type=Topic&f%5B0%5D.Value=Sharepoint%202010%20101%20code%20samples&f%5B0%5D.Text=Sharepoint%202010%20101%20code%20samples
Or download the hole bunch here http://code.msdn.microsoft.com/SharePoint-2010-101-Code-da251182