cannot upload into media library

been messing about with the media library for the last few hours and i cant get it to upload. im assuming you can manually upload via scp or whatever ? i put the file in any of the directories and i cannot see them with the media library. ive tried two .flv files and one .jpg file. what am i doing wrong ?

ive read all the posts on changing your permissions to 777 (ahem) but theres nothing wrong with my permissions and i can upload to the directory fine through the admin panel. i just want to upload some files that are bigger than my 7mb limit.