All newsletter subscribers have an account created for them (don't worry, it's free to subscribers) automatically when a subscription is created. FeedBlitz uses this account to keep all your subscriptions and other preferences together so that you can manage them easily.
When an account is created automatically to handle your first subscription, FeedBlitz creates an automatic password from random letters and numbers. You can retrieve your current FeedBlitz password at www.feedblitz.com/f/f.fbz?MailPwd
There is no need to register for a FeedBlitz account in order to set up a subscription to a web site.