Are you doing forms over data apps?
Well in that case you might want to check out these videos. There are 8 of them at the moment and they show how to do the most common tasks. These videos are created by Beth Massi of the Visual Basic team so all the code is in VB but even if you are a C# developer they are real useful!
Update: It is kind of useful to include the link 
so here it is http://msdn2.microsoft.com/en-us/vbasic/bb466226.aspx.
Recommended!