(Password) Salt Storage

Hi;

I'm a bit of a .NET / VB novice so do please indulge my ignorance.  This is my problem:

I'm trying to create a custom membership provider.  I want to model my tables and programability (stored procedures etc...) on those distributed by Microsoft.  Now, the aspnet_Membership table (which I've copied [and renamed] into a DB of my own, to avoid any future conflict with Microsoft) requires a PasswordSalt field (which is not nullable).  I'm trying to generate, retrieve and store this value but I seem not to be able to retrieve it in a manner to be stored as NVarChar in the DB.  I use this code to do the hashing:

Dim hash As HMACSHA1 = New HMACSHA1()

encodedString = Convert.ToBase64String(hash.ComputeHash(Encoding.Unicode.GetBytes(aString)))

That's fine.  Now I want to get the key/salt (are these the same thing?) to store in my DB table.  An e ...