If your password is "unforgotten" then you don't need to retrieve it. Otherwise, if you have forgotten it, I believe Skype, like most other websites, has a link that you can clik below or near where you would enter your password, that you can ask them to send you your lost password, however, I should add, this will only work if you actually used your personal email or an email account that you have access to. If you used a false email address, then of course, they would send your password, forgotten or otherwise, to that email address.
