Openly Published e-Commerce Security Precautions?

zCyl asks: "When I went to purchase a SCSI card online a while back, I went to a dealer that I had heard was reputable. Then a little later they were purchased by Egghead, and I was added to the Egghead database and I unwittingly became one of the millions of customers who were notified that the Egghead database containing their information had been compromised. How are those of us who do understand computer security and could evaluate the security of an e-commerce site supposed to determine the security of the sites we purchase products from? Are there any existing e-commerce sites that openly publish the precautions and security measures they take to ensure the safety of the information I entrust to them while making a purchase?"