You can get it where you get the database version dear
search for download at technet.oracle.com.

By the way people, why is it that in my 9i-cleint I can update,insert,delete
rows using the database tree navigator pane drilling down to the table level.
But now in 10g client It doesnt allow me anymore to edit rows. Why is that
it keeps on getting less functional while they upgrade this client thing

Thanks