The easiest way to order the Pushpin Tool for MapPoint 2006/2009 is from the store on MapForums at www.mapforums.com/mappoint.php
Where you see Pushpin Tool, click on Add to Cart on the right side. You can also pick up a copy of MapPoint for Dummies, Programming MapPoint in .NET, or one of several other items.
The orders are routed through Paypal which accepts any credit card.
Multiple user discounts are also available. Have fun and let me know if you have any questions.