C sharp,dataset and xml

Do as SA suggests.
Some good links are LINQ to XML[^] for storing and retrieving XML data in a file and SqlConnection[^] database connection (but it depends on what type of database you use)

As I said in my comment, you'll find lots of ideas in Google. You mentioned that you dont have any idea on how you will do your project. You need to do some reading about how software applications are being created(i.e. from planning phase to implementation and maintenance). Assuming you are going to use C#(as what is indicated in the tag), you might also need to read about ADO.Net. See below link. It has also some sample codes for you to have a headstart.

Using ADO.NET for beginners[^]

see these links:

http://msdn.microsoft.com/en-us/library/ms187339.aspx[^]

http://msdn.microsoft.com/en-us/library/ms345117(SQL.90).aspx[^]