Here is the link to the Realtor 2005 Cost vs. Value Report: 

The article details 10 home improvements and whether or not you can recoup the cost of those improvements when you go to sell your home.  For the most part, you'll find that most projects will not add more than the cost of the project to the value of your home, which isn't to say they won't make your home more appealing and easier to sell.  Read on for details...

http://www.realtor.org/rmomag.NSF/pages/feature1dec05?OpenDocument

Source: Realtor.org and Realtor Magazine, Dec. 2005