need help debugging pls

 i am going a little crazy here...
 here is my code for a function...
when it gets to line 37 it goes to an exception saying
exception    {"Object reference not set to an instance of an object."}    System.Exception {System.NullReferenceException}

I have no idea why...

1 public string [][] albums;
2 ..
3 ...
4
5 ...
6 protected string [][] getAlbums(string userid)
7 {
8
9 dbOperations dbo = new dbOperations();
10
11 try
12 {
13
14 db ...