It is possible to obtain records from some databases by first connecting to them, and then searching, via the EndNote Online interface.
As you are likley to use only selected online search connections provided in EndNote Online it is a good idea to create a list of favourites for easy selection.
Note: As there are no sign-in details contained in the connections, only freely available sources will be accessible to you. The exception is Web Of Science citation indexes. If you have registered for EndNote Online via Web of Science there is a link to Web of Science at the top of the screen which will link into the entire database.
* see the 'Organising and sharing your references' tab in EndNote Online - The Basics for how to set up groups
Web of Knowledge / Web of Science provides for direct transfer of records into EndNote Online.