Hey John,
I've been looking for this issue at B&N without finding it either. The article features two beautiful cars, an Evo II and a Sport Evo, that have the AN conversion by tuner Paul Shepherd which uses the Rongineer M3 Airbox. Paul's getting terrific performance improvements with his system.
I have scans of the article which I put on my website with permission from BMWCar magazine. You can see them here:
www.rongineer.com/products.html.
FYI, there's also an article about these cars in the January issue of the UK BMW Car Club magazine called Straight Six. It's even more informative, but approval is still pending...will release when received.
Enjoy,
Ron