How do I link two different datasets by a unique variable?

As I believe you are looking for something like this - Master/Detail Using a Selectable Master GridView with a Details DetailView:

http://msdn.microsoft.com/en-us/library/aa581795.aspx

Am I right?

I can't seem to locate GridView in my toolbox. I'm working with SQL Server 2005 - SQL Business Intelligence Development studio.

To give you more detail. My report with the claim information has several different columns for one claim and the diary detail has more than one entry for each claim. Each of the entries has it's own list of columns. I would like the user to be able to view the claim number and claim information then be able to hit a toggle or link that will expose all of the dairy entries attached to the specific claim number. I'm very beginner so step by step instructions would be great.

Can anyone help me?

Gridview control you can find in Visual Studio toolbox among data controls. You have to open aspx page in design view (for web projects, or datagridview for winform project)  to enable this control on toolbox. But my question is: do you use visual studio? You write in you first post that you use it, but later you have written that you use only Sql Server 2005?

It is Sql server reporting services; however opens into a visual studio window. I have attached a screen print of the current report that I'm working on. I don't know how to open in an aspx page?
VisualStudio.doc