If you are interested in learning more about the Entity Framework you need to visit Zeeshan Hirani’s Blog and download an e-book that he made available for free. It’s a problem solution approach to explain the EF in good detail. The book has 514 pages of lots of good information.
You might also like to watch the two short videos on the EF available at the asp.net site. Here are the links:
Get started with the entity framework
Use the new Entity Data Source