LINQ is one of the new feature we will get in .NET 3.5. I think it's a very interesting new technology that consist of LINQ the language, and some elements that make use of LINQ for use with XML files or databases. LINQ to SQL is one of the techniques to use LINQ to communicate with the database. There are a few other techniques that use LINQ in combination with the database: LINQ to Entities, LINQ to Dataset. I started with the 5 part LINQ to SQL series by Scott Guthrie:

1. Using LINQ to SQL
2. Defining our Data Model classes
3. Querying our Database
4. Updating our Database
5. Binding UI using ASP:LinqDataSource control