With all fairness they went under not because of their advertising practices, but because they spent to much time developing games and not releasing games.
Decent
Decent II
Decent III
Decent Freespace
Freespace II
Bolders Gate
Bolders Gate II
Star Fleet Command
Star Fleet Command II
Were all excellent games with effective advertising. But since then, NOTHING. What really hurt Interplay was the lack of support for their games.