This has bugged me for a while but as with most things it's easy when you know how.
First setup a crom job with wget
0 */6 * * * wget -A torrent -r -l 1 http://ewheel.democracynow.org/
(-l is a small L) as in go down one level
This will go an check for new torrents every 6 hours at http://ewheel.democracynow.org/ and place them in a directory of the same name in your home directory.
Now just set transmission to watch that folder
edit > preferences > automatically add torrents from > ewheel.democracynow.org
Do not set transmission to delete the torrents or wget could fetch them again!! Wait until they're removed from the site if you really must.