Insert, Conditions, 3 Tables, Syntax, Performance

The following code should insert into 3 tables based on conditions. There's something screwy in my syntax and I'm pretty new at this can anyone help with transforming this in terms of performance and being syntactically correct? Thanks a million!


CREATE PROCEDURE [insert_vwMusic]
(@Artist [nvarchar](50),
@Genre [nvarchar](50),
@NLink [nvarchar](50),
@Album[nvarchar](50),
@Song[nvarchar](50),
@ArtistID[nvarchar](50),
@AlbumID[nvarchar](50),
@SLink[nvarchar](50))

AS

DECLARE @NewArtistID VarChar(50),
DECLARE @NewAlbumID VarChar(50)

IF Not Exists (SELECT [Artist] FROM [integration].[dbo].[tblMusic_Artist] WHERE [Artist] = @Artist)
BEGIN
INSERT INTO [integration].[dbo].[tblMusic_Artist]
( [Artist],
[Genre],
[NLink])

VALUES
( @Artist,
@Genre,
@NLink)

SET @NewArtistID = @@IDENTITY

INSERT INTO [integration].[dbo].[tblMusic_Albums]
( [Album]

VALUES
( @Album)

SET @NewAlbumID = @@IDENTITY

INSERT INTO [integration].[dbo].[tblMusic_Song]
( [Song],
[ArtistID],
[AlbumID],
[SLink])

VALUES
( @Song,
@NewArtistID,
@NewAlbumID,
@SLink)
END

ELSE
BEGIN
IF Not Exists (SELECT [Album] FROM [integration].[dbo].[tblMusic_Album] WHERE [Album] = @Album)
BEGIN
INSERT INTO [integration].[dbo].[tblMusic_Albums]
( [Album]

VALUES
( @Album)

SET @NewAlbumID = @@IDENTITY
SET @NewArtistID = (SELECT [ID] FROM [integration].[dbo].[tblMusic_Artist] WHERE [Artist] = @Artist)

INSERT INTO [integration].[dbo].[tblMusic_Song]
( [Song],
[ArtistID],
[AlbumID],
[SLink])

VALUES
( @Song,
@NewArtistID,
@NewAlbumID,
@SLink)
END
END
ELSE
BEGIN
SET @NewAlbumID = (SELECT [ID] FROM [integration].[dbo].[tblMusic_Album] WHERE [Album] = @Album)
SET @NewArtistID = (SELECT [ID] FROM [integration].[dbo].[tblMusic_Artist] WHERE [Artist] = @Artist)

INSERT INTO [integration].[dbo].[tblMusic_Song]
( [Song],
[ArtistID],
[AlbumID],
[SLink])

VALUES
( @Song,
@NewArtistID,
@NewAlbumID,
@SLink)
END

GO