Maintaining the theme from my earlier post on SQL Injection application vulnerabilities, take a look at the following Patterns and Practices How Tos...

How To: Protect From Injection Attacks in ASP.NET (PAG Documentation):
http://msdn.microsoft.com/library/en-us/dnpag2/html/PAGHT000003.asp?frame=true&_r=1

How To: Protect From SQL Injection in ASP.NET (PAG Documentation):
http://msdn.microsoft.com/library/en-us/dnpag2/html/PAGHT000002.asp?frame=true&_r=1

How To: Use Regular Expressions to Constrain Input in ASP.NET (PAG Documentation):
http://msdn.microsoft.com/library/en-us/dnpag2/html/PAGHT000001.asp?frame=true&_r=1

 

Also check out the following Blackbelt Web Cast:

Defending the Database (Part 1 of 2): The SQL Injection Attack in Detail (Level 300) http://www.microsoft.com/events/EventDetails.aspx?CMTYSvcSource=MSCOMMedia&Params=%7eCMTYDataSvcParams%5e%7earg+Name%3d%22ID%22+Value%3d%221032267307%22%2f%5e%7earg+Name%3d%22ProviderID%22+Value%3d%22A6B43178-497C-4225-BA42-DF595171F04C%22%2f%5e%7earg+Name%3d%22lang%22+Value%3d%22en%22%2f%5e%7earg+Name%3d%22cr%22+Value%3d%22US%22%2f%5e%7esParams%5e%7e%2fsParams%5e%7e%2fCMTYDataSvcParams%5e