If you've already signed up for a Lend Library account, then you'll find your log in screen from your library's own Lend Library 'member site'.
When you registered, you chose a domain, which is where your member site can be found.
It will be similar to http://MYDOMAIN.lend-library.co.uk, and is also in the welcome email we sent you when you activated your account.
If you've forgotten, or lost that email, just contact us and we'll help you out.