Since in sarepoint everything is diffrentiated with a GUID,many a times you are required to get the GUID of say a list.The usual way is to write a small console application to get the GUID of the list...a quick way is
1.Go to the list
2.Go to list settings
3. see the URL, it would be something like
4.Copy the value after List= ...
5. Remove startin and ending %7B and %7D
6.Replace %2D with -