There is a great collection of 101 LINQ samples under C# development center on MSDN. Samples are grouped into restriction, grouping, aggregate, projection, set conversion, partitioning, element, ordering, generation, custom sequence and other operators. Each sample consist of source code, description and a result set. 101 LINQ samples are available here.
There are even more LINQ examples on MSDN Code Gallery published by independent developers.
If you are not familiar with LINQ, read my previous posts LINQ to SQL Overview and Importing/exporting XML data using LINQ.
