Question: Where would the physical files be?

Answer: 
```
System.Diagnostics.Process.Start(
    Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) + 
    "\\IsolatedStorage"
    );

```
On my XP workstation I found it under c:\Documents and Settings\\Local Settings\Application Data\Microsoft\Silverlight\is\XXXXXXXXXXXXX
Where xxxxxxxx appears to be a random directory name. (under that if you wander around enough you should find the store for your particular app...)