Currently (CiviCRM 4.0.0) the available event listings do not represent whether an event is fully-booked in the listing itself. Users must click on an event before being told that an event is fully-booked on the event info page. This is because it is not a straightforward database query to find out if an event is fully booked as there are multiple factors such as pending places to take into account. This page shows a way to use the Drupal Views PHP module to create an event listing incorporating a fully-booked flag.
After all that here's the sort of page we can generate...