If you press on any one of the goods liste at this website, you will be carried directly inside ebay. If you don't feel secure in inputting your own credit card information when purchasing from a new site, you may go for a third party payments service just like PayPal when paying your online purchases. Such payment method will prevent the vendor from seeing any important information about you.
When applying for a membership, sometimes a lot of questions are asked regarding private information. In spite of this, you do not need to fill out all field but just those which are required will suffice.