A quick search didn't seem to show anybody's experience with the Costco Buying Program so I thought I'd plug it here. I had a very, very good experience and seemed to save me more than I could had I gone in and spent hours negotiating. See my thread for a detailed description. I wish I had used the service in the past as it probably would have saved me a lot of money.
viewtopic.php?f=40&t=39494&p=471479#p471479" onclick="window.open(this.href);return false;