There is no SCOPE_IDENTITY() equivalent when using GUIDs as primary keys, but you can use the OUTPUT clause to achieve a similar result. You don't need to use a table variable for output.
CREATE TABLE dbo.GuidTest (
GuidColumn uniqueidentifier NOT NULL DEFAULT NewSequentialID(),
IntColumn int NOT NULL
)
GO
INSERT INTO GuidTest(IntColumn)
OUTPUT inserted.GuidColumn
VALUES(1)
The example above is useful if you want to read the value from a .Net client. To read the value from .Net you would just use the ExecuteScalar method.
...
string sql = "INSERT INTO GuidTest(IntColumn) OUTPUT inserted.GuidColumn VALUES(1)";
SqlCommand cmd = new SqlCommand(sql, conn);
Guid guid = (Guid)cmd.ExecuteScalar();
...