There are a couple of methods you can use to give passwords to visitors who would like to view your Yahoo! Store.

To give visitors an information page with no password, you can set up a second Yahoo! Store account, and create links from there to your password-protected account. This way, visitors to your site can see your front page with information about how to subscribe or obtain a password.

If you were limiting viewing privileges to specific people, you could also send each individual a custom email with the ID and password to view your store. However, you should make sure that you don't mass-email (spam) potential visitors, as Yahoo! Store has a firm anti-spam policy.