SQL Server 2000 / ADO.Net / VB.Net / DataGrid

I am a newbie to ADO.net and disconnected data. Even though I have done
a lot of reading I have not been able to get the following questions
answered.

I don't understand how a disconnected dataset is supposed to get the id
field value assigned. In sqlsvr2k the id field is assigned as an
identity with a seed value and an increment. Does the dataset know that
when it isn't even connected to sql server where the identity
constraints are defined?

I thought... maybe the dataset is smarter than I realize I'll just try
it.

Well I tried it. I can't get it to work!

More description:
Because the ID is defined as an identity it also is "NOT NULL". I can't
create a record in the Datagrid without the system stopping me to tell
me the ID is null - and of course it will not let me assign a value to
it either.

1.) So... What's the secret?

I understand in a disconnected environment that concurrency is an issue
that needs to be dealt with but you still need to somehow get a value
into the id field to start with.

2.) And while you are at it please clear up a related mystery for me.

In a disconnected dataset environment how can vb.net or ado.net deliver
the customer_id (of a customers table) to the foreign key
(fk_customer_id) an orders table?? It may not even exist yet in many
scenarios.

=============================
Below is my table. As you can see RefSourceID is an Identity and SQL
Server should deliver the next value to it.

CREATE TABLE [dbo].[lkp01RefSource] (
[RefSourceID] [tinyint] IDENTITY (1 ,1) NOT NULL,
[RefSource] [varchar] (25) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL
, -- The display name of the table,
[ord] [tinyint] NOT NULL DEFAULT 0, -- sort first by ord then by name,
[hide] [bit] NOT NULL DEFAULT 0,
) ON [PRIMARY]
GO

In vb.net I had the data adapter configured to create a stored
procedure.

My note in the stored procedure below helps to illustrates some of the
mystery to me.

=====================================
CREATE PROCEDURE [dbo].[RefSourceInsertCommand]
(
    @RefSourceID tinyint, -- << What is this? No accomodation for sql
generating its identity
    @RefSource varchar(25),
    @ord tinyint,
    @hide bit
)
AS
    SET NOCOUNT OFF;
INSERT INTO lkp01RefSource(RefSourceID, RefSource, ord, hide) VALUES
(@RefSourceID, @RefSource, @ord, @hide);
    SELECT RefSourceID, RefSource, ord, hide FROM lkp01RefSource WHERE
(RefSourceID = @RefSourceID);
GO
=====================================
If code creates the identity then there are conflicts to deal with if
other is adding records at the same time.

In answer to #2 above. Can't vb ask for and ID immediately before
continuing to build the record. (of course there can be no "NOT NULL"
fields with that scheme)

Please help me understand this or direct me to an article that
definitively answers this.