LINQ
LINQ (Language Integrated Querying) is a new technology promoting SQL querying to a first-class element of your code. This means that you can now refer to tables as classes within your code. Similarly, fields become properties of those classes. LINQ also add new syntax to perform querying rather than having to code SQL embedded in your code. You can also call stored procedures and views, if that's the way you want to go.
LINQ - simple intro. to concepts (Anders Heljberg) 
Slides on LINQ 101 (Anand Lyer web)
LINQ Hands-On Lab (pdf) (Microsoft) - comprehensive walkthrough w/ code
VS08 Enhancements (pdf) (Microsoft) - VS08 changes that support LINQ
101 LINQ Samples (Intro ) (Charlie Calvert ) - useful app showing results from many LINQ queries
Scott Guthrie video on LINQ (blog)
LINQ videos (4 parts) (Mike Taulty)
How to: Bind to the Results of a LINQ Query in WPF (MSDN) walkthru code : simple WPF/LINQ binding app.
Video How to: Writing Queries in C# (Walkthru) (LINQ) (MSDN)
Wrox VB.NEt & C# LINQ Talk (66min.) code camp : 2006 video on LINQ
Connecting SQL Database with LINQ to SQL Designer (Charlie Calvert): very short but practical walkthu of basics.
Data Binding (General - not LINQ specific)
Binding a CLR object to a custom list box (Todd Miranda)
Binding a CLR object to a list box in code (no Blend) (ContentPresenter.com)
Data Binding Samples (MSDN) : Long list of sample apps showing various data binding (inc. LINQ)
Basic SQL Server 2005 access (real simple!)
Data Validation
Data Validation (The Joy of Code) - Simple introduction
Data Validation using IDataErrorInfo (CodeGod) - using IDataErrorInfo rather than derivatives of ValidationRuleOld Material (retired)
Binding user controls to SQL Using ADO.NET (MSDN Bob)
Introduction to Data Binding (Akadia.com)