Freesound (http://freesound.iua.upf.edu/) is an online database with thousands of soundfiles which can be freely used in many projects (visit Freesound for the exact licensing terms). Ardour has an option to download files directly from freesound directly from the import dialog. Freesound files are tagged with metadata which you can use to search for relevant sounds.

To enable the Freesound search engine inside Ardour, you must build Ardour with the option FREESOUND=yes, and you must have the "curl" library installed. This is currently optional but may later become a standard feature of Ardour.

To download files from Freesound, you must first register for a username and password on the freesound website. Enter this information into the text entry boxes, enter your tags to search for, and then click "Start Downloading". Ardour will begin downloading files, and the "Start Downloading" button will change to say "Cancel". Clicking the "Cancel" button will wait until the currently downloading file is finished, then the button will switch back to "Start Downloading". The button will also say "Start Downloading" once Ardour has downloaded all of the files that match the given tag. In the future there may be better indication of the file progress and better filtering on the filetypes that are downloaded.

If you later search for the same terms, you will see that the files appear in the list more quickly, because any files in the search set that are already downloaded won't have to be downloaded again.

Sounds that are downloaded from Freesound will automatically be given tags in Ardour that match their tags in the Freesound database. This means that once they are downloaded, Ardour can search for the local files very quickly using the "Search Tags" tab.